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CNN Live Event/Special

Columbia: The Shuttle Tragedy I

Aired February 01, 2003 - 20:00   ET

THIS IS A RUSH TRANSCRIPT. THIS COPY MAY NOT BE IN ITS FINAL FORM AND MAY BE UPDATED.

THIS IS A RUSH TRANSCRIPT. THIS COPY MAY NOT BE IN ITS FINAL FORM AND MAY BE UPDATED.


(BEGIN AUDIO CLIP)
UNIDENTIFIED MALE: Columbia, Houston, we see your tire pressure messages and we did not copy your last.

UNIDENTIFIED MALE: Roger ...

(END AUDIO CLIP)

ANNOUNCER: The final moments before a national tragedy. Heading home, shuttle Columbia breaks up in mid-air.

(BEGIN VIDEO CLIP)

GEORGE W. BUSH, PRESIDENT OF THE UNITED STATES: At 9:00 this morning, Mission Control in Houston lost contact with our space shuttle Columbia. A short time later, debris was seen falling from the skies above Texas.

The Columbia is lost. There are no survivors.

(END VIDEO CLIP)

ANNOUNCER: Seven crew members lost. NASA officials begin a daunting investigation.

(BEGIN VIDEO CLIP)

CAPT. BILL READDY, ASTRONAUT, U.S. NAVY (RET.): My promise to the crew and to the crew families is that the investigation that we have just launched will find a cause. We'll fix it. And then we'll move on.

(END VIDEO CLIP)

ANNOUNCER: Tonight, a CNN Special Report -- "Columbia: A Shuttle Tragedy." From the CNN center in Atlanta, here's Miles O'Brien.

MILES O'BRIEN, CNN ANCHOR: Good evening. In the 42 years of U.S. human space flight, there had never been a fatal accident during the decent to earth or in landing. But this morning, that all changed.

Sixteen minutes before it was scheduled to touch down in Florida at the Kennedy Space Center, the space shuttle Columbia fell apart in the skies over Texas. You're looking at some animation developed through the good graces of analytical graphics. And what you see is the general scenario that occurs on re-entry, as the space shuttle returns from space, traveling at some 17,500 miles an hour, breaking its way toward the runway at the Kennedy Space Center on the Florida peninsula -- pitching, nose high up, presenting to the strongest portion of the heat those black tiles, there to insulate the space shuttle, which is, after all, an aluminum frame aircraft, from the 3,000 degree heat of re-entry.

It was at the absolute apex of that heat -- mach 18, 200,000 feet and change -- when the space shuttle Columbia disintegrated high over Texas.

This scenario is being watched very closely in Houston right now. There's a mission evaluation team right now poring over data which was captured immediately after it became apparent that there was a catastrophic failure of the space shuttle Columbia.

I'm told that mission managers will be looking very closely, and the engineers will be looking closely at what happened to the elevons. These are the flaps in the rear portion of the space shuttle Columbia.

There is some indication now, based on the preliminary look at the data, that there was some unusual movement by these elevons -- perhaps something that might have caused an abrupt maneuver -- very early in this investigation. But that is one of the things being looked at as they burn the midnight oil in Houston in the mission evaluation room.

In the morning there will be a series of meetings -- 8:00 a.m. local time, 9:00 a.m., 10:00 a.m. -- series of management meetings and engineering meetings to look at the data preliminarily, get a sense of where they're headed, and then in the noon hour, Central time, they will report back to reporters with another briefing, to give us a better sense of where they're headed with this investigation -- still, obviously, in the very early hours.

Coming up in the next hour of this program, extensive coverage of the Columbia tragedy and what might have gone wrong.

Also anchoring tonight's coverage, Wolf Blitzer live at the Johnson Space Center in Houston, Lou Dobbs from the Kennedy Space Center in Florida, and following the Bush administration's reaction, Judy Woodruff in Washington.

First, let's quickly update you on the very latest. All future space shuttle flights are now on hold until NASA gets a better grip on what went so terribly wrong this morning, as you see in these pictures, breaking up south of Dallas.

Space agency officials say not to worry, though, about crew members still aboard the international space station. They have enough supplies to last until June.

FEMA, the Federal Emergency Management Agency, has been put in charge of recovering and collecting the debris over a tremendously wide swath of the continental United States. The military has been called in to help that search.

They're concentrating on eastern Texas, bits and piece of the shuttle -- pieces of the shuttle -- have also been found in parts of Louisiana.

And, experts say, that because Columbia broke up at 200,000 feet, the debris field could extend to, even into Arkansas, Arizona and New Mexico.

Outside NASA headquarters and at the White House, flags flying at half-staff -- a tribute to the seven astronauts on board the space shuttle Columbia.

Many of the crew's relatives were at the Kennedy Space Center excitedly awaiting the touchdown -- a touchdown which never came -- after a 16-day science mission, which by all accounts was nearly flawless.

This was the 28th mission for the space shuttle Columbia -- focused on science, as we told you -- and Israel's first astronaut in space.

(BEGIN VIDEO TAPE)

UNIDENTIFIED MALE: ... three, two, one. We have booster ignition and liftoff of space shuttle Columbia with a multitude of national and international space research experiments.

O'BRIEN (voice-over): 10:39 a.m., January 16th. Columbia takes off.

UNIDENTIFIED MALE: ... now controlling the flight of Columbia, the international research mission finally underway. Commander Rick Husband joined on the flight deck by pilot Willie McCool, flight engineer Kalpana Chawla and mission specialist Dave Brown. Mission specialist Laurel Clark, payload commander Mike Anderson and payload specialist Ilan Ramon, seated down on the mid-deck.

O'BRIEN: 10:41 a.m. About 80 seconds into the flight, a piece of debris on the external fuel tank comes off, hitting the underside of the orbiter left wing.

There is some concern about overheating during re-entry if enough tiles are knocked loose. But after studying the images frame by frame, NASA engineers decide to continue the mission.

3:10 p.m., January 25 -- one week into the mission. The crew gives CNN an update from space.

RICK HUSBAND, SHUTTLE COMMANDER, SPACE SHUTTLE COLUMBIA: ... up here. We had a great ride to orbit, and all the activation of the experiments in the SPACEHAB went extremely well. And we're really -- we've got our space legs and up and running.

O'BRIEN: Another week passes. Saturday morning, February 1. The crew is just hours from returning home.

LAUREL CLARK, ASTRONAUT, SPACE SHUTTLE COLUMBIA: Good morning, Houston. We're getting ready for a big day up here. Had a great time on orbit. Really excited to come back home.

O'BRIEN: 8:15 a.m., while still in orbit, Columbia fires its breaking rockets. Its touchdown sequence is underway. It begins re- entry.

8:59 a.m. Mission Control hears from Columbia for the last time.

UNIDENTIFIED MALE: And Columbia Houston, we see your tire pressure messages, and we did not copy your last.

UNIDENTIFIED MALE: Roger, ...

O'BRIEN: 9:00 a.m., just 16 minutes away from its scheduled touchdown on Florida's east coast, Mission Control in Houston loses all data and voice contact with Columbia.

The shuttle is seen in the skies above Dallas, Texas. At this point, the spacecraft is roughly 203,000 feet above the earth, traveling about 12,500 miles an hour.

Residents across Texas, Arkansas and Louisiana see what NASA is not yet talking about.

UNIDENTIFIED FEMALE: We were woken up by this rumble. Today we were trying to sleep in on Saturday. And we heard this -- sounded like a train going through our property.

UNIDENTIFIED FEMALE: The dogs started barking and then got shook -- like shook the earth.

UNIDENTIFIED MALE: And we seen large masses of pieces coming off of the shuttle.

UNIDENTIFIED FEMALE: I'm devastated. Devastated. It's unbelievable.

O'BRIEN: And the National Weather Service even picks up these images on radar.

UNIDENTIFIED MALE: That is the wreckage of the shuttle Columbia coming through ...

O'BRIEN: 9:20. Quiet disbelief in the control room in Houston -- and from onlookers at the Kennedy Space Center.

UNIDENTIFIED MALE: We're shocked. We're -- we -- at a loss for words. We don't know what to think. We feel so sad and sorry for the families of people that have been lost. Just hope they're with God.

O'BRIEN: 9:29 a.m. NASA declares an emergency. Calls reporting debris hitting the ground flood police, NASA and newsroom phones.

9:44 a.m. NASA warns residents to stay away from the debris, which could be dangerous, because of toxins in the propellants used.

11:00 a.m. A flag at the Kennedy Space Center next to the countdown clock is lowered to half-staff.

1:30 p.m. NASA Administrator Sean O'Keefe.

SEAN O'KEEFE, NASA ADMINISTRATOR: We trust the prayers of the nation will be with them and with their families.

And, again, a more courageous group of people you could not have hoped to know -- and the families of these crew members.

An extraordinary, extraordinary group of astronauts who gave their lives.

O'BRIEN: 2:05 -- the President addresses the nation, delivering the gravest news.

BUSH: This day has brought terrible news and great sadness to our country.

The Columbia is lost. There are no survivors.

(END VIDEO SEGMENT)

O'BRIEN: At Mission Control in Houston, the first indication of trouble this morning was the loss of temperature sensors on Columbia's left wing, almost as if the plug had been pulled.

This was followed within seconds by a series of other problems. Wolf Blitzer joining us live now from the Johnson Space Center in Houston -- Wolf.

WOLF BLITZER, CNN ANCHOR: Miles, as you well know, this is a small family, all the people involved in this mission control operation here.

And there's tremendous, there's especially severe sadness here, because the seven astronauts had trained here in Houston at the Johnson Space Center. Their families, by and large, were here. They had had spent a long time getting ready for this mission. And everyone here is, as they've said to me, that words can't describe how upset, how sad they are at what's going on.

And spontaneous memorial services are erupting, even outside the gates of the Johnson Space Center here in Houston, Texas.

Now, they are urging the public to try to help if they can. They know there are hundreds, perhaps thousands of pieces of debris out there. They know that the public saw the images of the debris landing in central Texas, northern Texas -- all over here, all the way over to Louisiana.

They are asking, anyone has any film, any video, there's two ways of getting in touch with NASA officials. You can either call them at a number we've been putting up on the screen, 281-483-3388. I'll repeat that, 281-483-3388.

Or, you can e-mail them if you believe you have some information that could help the investigators. Their e-mail address is columbiaimages@nasa.gov.

Columbiaimages -- all one word -- @nasa.gov.

Now, Ed Lavandera has been out there in Texas. He's been talking to people who have seen some of the debris. Ed Lavandera is joining us now live from Nacogdoches.

Ed, tell us what you've seen and what you've heard.

ED LAVANDERA, CNN CORRESPONDENT: Well, Wolf, what we've seen throughout the day is many people -- actually closer to the Dallas- Fort Worth area, many people were paying attention to this shuttle landing today. Just kind of the course of events today, kind of everything lined up nicely.

It was a beautiful day here weather-wise in Texas, and many people were able to see. One of those great moments where you could see the space shuttle streaking across the State of Texas as it was headed toward Florida for its final approach.

And so, a lot of people watching the live coverage on the local newscast, that as the shuttle was streaking overhead here. So that was a very strange moment, not something -- a very unique moment, I should. Not a chance that a lot of people get to see.

So we are about 3.5 hours southeast of the Dallas-Fort Worth hour, and about another three hours north of Houston, to kind of pinpoint you. And we're in the center of Nacogdoches, Texas.

And this has kind of become a nerve center, if you will, for a lot of people who have come here.

And the reason they're here is, this one parking lot, is there's just a three-by-three-foot piece of debris there. And this is very significant of what we've seen throughout the East Texas area.

In people's backyards, driveways, sidewalks, the back roads of East Texas have seen small parts of debris like this scattered all over the place. When we've seen the areas cordoned off just like this, and many times we've often seen private landowners.

They are doing the same -- waiting for authorities to come by and pick up this material. We understand that they're trying to line up the process by how exactly they're going to do this.

I've also had a chance to speak with other people who say that they have seen debris in the back of their businesses and their homes, as well. And that, I guess, there's just so many calls that have been coming into the authorities here in the East Texas area that it's been impossible to get somebody out to all of these locations at this point so far. So there's a lot of work still left to do here, Wolf.

BLITZER: Ed, to people understand, by and large, how dangerous it is, these toxic propellants as they call it. That if anybody gets too close or touches the kind of debris, they could be in trouble?

By and large, has that message gotten through?

LAVANDERA: You know, for the most part I have seen that -- you'll be driving around a neighborhood and you'll see a debris -- a piece of debris on the ground. And what you'll see is a lot of people gathered around, but they'll probably -- they'll keep a safe distance from it, not touching it.

A lot of people taking pictures of it. But for the most part, I think that word has gotten out that people should stay away.

BLITZER: And it is, of course, the property of the United States government. It would be a crime for anyone to take any of that debris with them.

CNN's Ed Lavandera joining us from Nacogdoches in Texas. Thanks very much, Ed.

And, Miles, when I throw it back to you, the -- as you well know, the investigators want to collect as much of that debris as possible. It's unclear whether they're going to try to recreate as best they can the Columbia. But they do want that debris, because there could be some telltale signs of what exactly caused this horrible explosion -- Miles.

O'BRIEN: Well, Wolf, as you well know, it's not an overstatement to say that this thing could be unlocked, the puzzle could be solved by simply one piece.

So, we encourage people, if they see pieces to let NASA know. Who knows what the significance of that piece might be?

We're going to take a short break. And when we return, we're going to go to Washington and check in with Judy Woodruff and talk about the President and the political implications of all this, as NASA embarks on efforts to fly one day again.

And we'll also check in with Lou Dobbs, who is at the Kennedy Space Center, where Columbia left 16 days ago in a blaze of glory.

Stay with us.

(COMMERCIAL BREAK)

O'BRIEN: We all knew it would happen. We just didn't know how.

That's the words of one NASA worker from Houston today, as they consider what happened, as the space shuttle Columbia came in on what seemed like the flawless conclusion to a nearly flawless mission. Let's continue our coverage as we turn our attention now to Washington and to Florida, on a story that really spans the entire country.

Lou Dobbs at the Kennedy Space Center, but first, Judy Woodruff in Washington -- Judy.

JUDY WOODRUFF, CNN ANCHOR: That's right. Thank you, Miles. And it has been a full day, and a very difficult day, for President George W. Bush, who, as we know, until just lately, his main focus has been pressing the U.S. case against Iraq.

Well, today, the President has talked by telephone with the families of the lost astronauts. He has spoken words of consolation to the rest of the country -- to all of us.

CNN's White House correspondent, Suzanne Malveaux, has been at the White House all this day following developments -- Suzanne.

SUZANNE MALVEAUX, CNN WHITE HOUSE CORRESPONDENT: Well, Judy, tonight leaders around the world are offering their condolences to the White House, as President Bush marks this tragic day with reflection, mourning and prayer.

(BEGIN VIDEOTAPE)

MALVEAUX (voice-over): In honor of those lost, the flag at the White House lowered at half-staff. President Bush, once again, charged with ...

WOODRUFF: Testing, one, two, three, testing ...

MALVEAUX: ... carrying out the somber duty ...

WOODRUFF: ... one, two, three, four, five ...

MALVEAUX: ... of bringing the nation together in times of tragedy.

BUSH: My fellow Americans, ...

WOODRUFF: Testing. You want it up higher?

BUSH: ... this day has brought terrible news and great sadness to our country.

WOODRUFF: Testing, one, two, three, four, five.

BUSH: At 9:00 this morning, Mission Control in Houston lost contact with our space shuttle Columbia. A short time later, debris was seen falling from the skies above Texas.

The Columbia is lost. There are no survivors.

MALVEAUX: Six Americans and one Israeli lost -- people the President said assumed great risk in the service to all humanity. BUSH: The cause in which they died will continue. Mankind is led into the darkness beyond our world by the inspiration of discovery and the longing to understand.

Our journey into space will go on.

MALVEAUX: Just after 9:00 this morning at Camp David, President Bush is notified by his chief-of-staff that NASA has lost contact with the shuttle.

At 10:30, he's briefed by NASA's director, and decides to return to the White House early. The situation room at the White House goes into full gear, notifying all the principals.

By 12:30, the president is back in the Oval Office, when NASA's director tells him there are no survivors.

Fifteen minutes later, Mr. Bush, standing at his desk, holds a conference call with the victims' families, who are gathered around a speakerphone at the Kennedy Space Center.

He tells them, "We express our love and appreciation for all those who died today. I want the loved ones to know there are millions of Americans praying for you, including me and Laura.

"It's an incredibly tough day for you. May God bless you all. I wish I was there to hug, cry and comfort you right now."

In a poignant moment, the White House aide who was with the President says after the call, a somber Mr. Bush briefly excused himself to the executive residence.

The president also called Israeli Prime Minister Ariel Sharon, to offer his condolences for the Israeli astronaut lost. And the President received calls from world leaders -- from Mexico, Canada, and even those recently at odds with the president over his stand with Iraq -- France and Russia.

(END VIDEOTAPE)

MALVEAUX: And, Judy, today was a big day for the Department of Homeland Security, as new Secretary, Governor Tom Ridge, able to quickly assess and gather information, assigned FEMA the lead role in recovery, and also to reassure the American people, that as tragic as this disaster was, it was not the result of terrorism -- Judy.

WOODRUFF: All right. Thank you, Suzanne.

At the same time, they are saying they are pressing ahead with the case against Iraq. That will continue.

Well, as you've been hearing from my colleague, Miles O'Brien, NASA's engineers are already hard at work trying to solve the mystery of what happened to the shuttle Columbia.

But a number of other federal agencies are also involved in the investigation. And for that part of the story, we're going to bring in our Patty Davis -- Patty.

PATTY DAVIS, CNN CORRESPONDENT: Well, Judy, FEMA is heading the response and recovery effort. Other agencies are heading south to take part in the investigation.

(BEGIN VIDEOTAPE)

DAVIS (voice-over): The debris strewn across several states is crucial of finding what caused the accident.

RON DITTEMORE, NASA SHUTTLE PROGRAM MANAGER: We are going to gather every piece we can find, treat this much like an aircraft incident, and see if we can solve the puzzle.

DAVIS: Finding the pieces is a massive undertaking, but an essential one.

If the cause is structural, debris could provide the key clues.

GUY GARDNER, FORMER SHUTTLE ASTRONAUT: They can then piece that together to figure out how it came apart. And then that'll help them figure out where the cause was.

DAVIS: That's why officials are appealing to the public to turn over any pictures people took of the shuttle falling, and to turn in any pieces found.

GOV. RICK PERRY, TEXAS: If you find debris, please call local authorities immediately to tell them of the location.

DAVIS: The Federal Emergency Management Agency is coordinating the federal government's response and recovery. The military guarding and searching for debris using planes, boats and helicopters.

The FAA instituting a 40-mile-wide, 160-mile-long restricted zone below 3,000 feet from Texas to Louisiana, to protect aircraft involved in the recovery.

The National Transportation Safety Board sending vehicle structure and system experts to help.

NTSB crash investigators helped piece together debris from the in-flight of the TWA 800 crash. This debris field as much as 100 times bigger.

PETER GOELZ, FORMER MANAGING DIRECTOR, NATIONAL TRANSPORTATION SAFETY BOARD: This is going to be an extraordinarily challenging investigation. The vehicle was at 200,000 feet. It was traveling at 12,500 miles per hour.

There certainly has never been a breakup by -- like this in aviation or space history.

DAVIS: In addition to debris, NASA says the shuttle had data and voice recorders. But more importantly, it was constantly streaming information to mission control. DITTEMORE: We are preserving hardware around the country in our different facilities. We are impounding data here that represented the last data that we received from the crew.

And we will be poring over that data 24 hours a day.

(END VIDEOTAPE)

DAVIS: Besides NASA's own investigation, an independent group, including the military, the FAA will also look into what happened -- an investigation that could take months, if not years -- Judy.

WOODRUFF: All right. Patty Davis, thanks very much. When you think about it, Miles, it seems almost a miracle that any pieces survived from that altitude and at that speed.

O'BRIEN: Judy, what I've seen is, there aren't many very big pieces. That is for sure.

Just 12 hours ago, hundreds of people were gathering at the Kennedy Space Center to see the shuttle landing. Their excitement quickly turned to shock.

CNN's Lou Dobbs is at Kennedy -- Lou.

LOU DOBBS, CNN ANCHOR: Miles, as you say, shock. And the shock is still being felt profoundly here by everyone who works at NASA, and who works with NASA.

The NASA administrator, Sean O'Keefe, has spent much of the day comforting the families of the seven astronauts who lost their lives today aboard Columbia.

He has also spent much of his time learning as much as possible about what the NASA engineers and managers and investigators know to this point. And he has been briefing congressional leaders, amongst them House Majority Leader Tom DeLay and Congressman Dave Weldon.

And I want to turn now, if I may, to John Zarrella, my colleague here who has covered the space program for some time.

This represents something of a departure, does it not. Sean O'Keefe has really opened up a process and is sharing information, which has not always been the first reflex at this agency.

JOHN ZARRELLA, CNN CORRESPONDENT: Right, exactly. And certainly back in 1986, that really was not the case back in 1986. It was far more of a closed family here, and they kept the information very close to the vest for quite some time.

But an open process here certainly.

DOBBS: John, I've just been told that our colleague, Gary Tuchman is available. Gary, let's go to you quickly.

GARY TUCHMAN, CNN CORRESPONDENT: ... happened today. We come to you from the Sunrise Diner in Cocoa Beach, just south of the Cape, where people are obviously talking about what happened today.

Right here we have Mike and Joanna.

Mike, you were telling me that Joanna, who is your friend, called you to tell you about the shuttle explosion. What did you think when you first heard it?

MIKE: At first I didn't believe it, you know. Shock and amazement. And then when I seen it was true, you think about the families and all that.

A very sad thing.

TUCHMAN: You tell me, when you live here, you just take for granted that the missions will all go OK.

MIKE: Yes, I mean, when I first moved down here, it was, oh, we had to watch every one come in. And then you just take for granted that they'll get here safely. And this time they didn't.

TUCHMAN: Thanks for talking with us.

We want to go over here. This is Frank and Marilyn. Frank and Marilyn live in New York State half the year, and they live here half the year.

And Marilyn was telling me that regularly, they go out on their balcony, on the ocean here, when the shuttle takes off and when it lands, right.

MARILYN: That's right. It's very exciting. And being away from this area, I don't take it for granted. I think it's so exciting to watch the shuttles when the rockets go up.

And we're on our balcony every single time.

TUCHMAN: Including this morning, right?

MARILYN: Including this morning. We were there ...

TUCHMAN: Tell me what happened this morning.

MARILYN: We were there at 9 o'clock, and I was looking out, looking at some people at the beach, and waiting for the sound of that beautiful -- I'm just really sad about this whole thing.

But I just -- my heart goes out to all of the people involved, the families especially, their children. And Israel -- I feel very sadly, because they have a hero. And India. And especially the United States.

I just -- I'm so sad for all of them. I think they're all heroes.

TUCHMAN: Frank and Marilyn, thank you very much for talking with me. It's obviously very emotional for then nation, for the world, but particularly for the people here on the space coast of Florida.

Lou, back to you.

DOBBS: Gary, thank you very much. Gary Tuchman in Coco Beach, Florida. Now, back to you, Miles.

O'BRIEN: All right. Thank you very much, Lou.

A check of the latest developments in today's shuttle tragedy is just ahead.

And the question burning on so many minds tonight. What went wrong up there?

We'll have a closer look at what we know at this time, obviously very early, and where authorities are focusing their attention as they work through the night tonight at Mission Control in Houston.

Plus, one of the crew members -- Israel's first astronaut. We'll have a live report from Jerusalem for a man who is -- was -- a national hero in that country.

And later, in their own words, family members who were expecting their loved ones to return home to earth this morning. Their thoughts and their feelings on this terribly tragic day.

(COMMERCIAL BREAK)

O'BRIEN: Welcome back. Investigators from the National Transportation Safety Board, NASA, the military and other federal agencies are trying to determine why the space shuttle Columbia broke apart this morning in the sky over Texas. All seven astronauts aboard were lost.

Columbia was at an altitude of some 39 miles, traveling 12,500 miles an hour when it broke into fiery pieces. It was absolutely the hottest point of re-entry, 3,000 degrees Fahrenheit. Parts of the shuttle have been found in east Texas and Louisiana. Some pieces were so hot that they caused fires, as you see here. The spacecraft was so high the debris field may extend into New Mexico and Arizona. Parts of what authorities suspect are human remains also have been found.

Now, as for the cause, several minutes before the breakup, there were some sensors on Columbia's left wing. They began failing, temperature sensors, specifically, toward the rear portion of the wing. Others registered high temperatures, and there are reports that there was some unusual movements of the flaps at the back called ailerons.

Memories have gone back to launch day, where cameras saw a piece of foam insulation from the fuel tank breaking off, hitting Columbia's left wing. The shuttle program manager, Ron Dittemore, says at this point not a smoking gun, but he adds, we cannot discount that there may be a connection.

And we should tell you, the person who will be heading this investigation. NASA has named a retired admiral who also headed the investigation into the explosion aboard the USS Cole in Yemen to lead the investigation. His name is Admiral Harold Gehman, and he will lead this independent investigation into determining the cause of the disintegration of the space shuttle Columbia. We will keep you posted on that.

A team of experts from the National Transportation Safety Board is heading for Barksdale Air Force base in Louisiana. That's where NASA has set up a command post. The NTSB will help the space agency in what is expected to be a lengthy and difficult investigation of this morning's disaster.

(BEGIN VIDEOTAPE)

O'BRIEN (voice-over): First things first. NASA starts eliminating possible causes.

SEAN O'KEEFE, NASA ADMINISTRATOR: We have no indications that the mishap was caused by anything or anyone on the ground.

O'BRIEN: From there, the potential causes are innumerable, given the one million parts and complex operations that go into any shuttle mission.

As rocket scientists like to say, it's always what you do not expect, because if you'd thought of it, you'd have fixed it.

One of the space shuttle program's greatest achievements was the development of the insulating tiles that protect the shuttle on re- entry. There are more than 20,000 of them on each shuttle, made of silicon fiber, they're cool to the touch just seconds after being exposed to a 2,200 degree kiln. While they have been a great achievement, they have been a continuing problem for shuttle managers. They're brittle and can easily be knocked off during launch. The shuttle can land if some insulating tiles are damaged or break off, as seen here on the space shuttle Discovery, but if too many tiles are gone, the shuttle would get too hot.

RANDY AVERA, FORMER NASA ENGINEER: The heat could actually cause the structure of the orbiter to break.

O'BRIEN: During Columbia's launch, a piece of insulation from the external fuel tank broke off and perhaps damaged some ceramic tiles, but shuttle managers determined it was safe for the mission to continue.

RON DITTEMORE, SHUTTLE PROGRAM MANAGER: We can't discount that there might be a connection. But we have to caution you and ourselves that we can't rush to judgment on it.

O'BRIEN: Another likely point of focus for investigators -- the altitude of the shuttle on re-entry. If the nose goes too high or too low, the shuttle could tumble and break up.

UNIDENTIFIED MALE: The belly of the shuttle is well protected, but if you get into wrong orientation at any moment during that re- entry, you are not protected on all sides, and so, you know, once you start coming apart, there is nothing you can do.

O'BRIEN: Columbia was the oldest shuttle. Just last year, engineers found stress and age cracks in shuttle's engine parts. While those problems, experts say, are not likely to be the cause of this disaster, there could be some other unforeseen, age-related problem with the shuttle. Whatever the cause, there may be clues in the data transmitted from the shuttle before communication was lost.

DITTEMORE: We will be poring over that data 24 hours a day fro the foreseeable future.

O'BRIEN: NASA has undertaken major investigations several times before; the last after the Challenger disaster.

Randy Avera worked on that investigation into why the Challenger disintegrated over the ocean shortly after liftoff.

AVERA: What we do not have as far as we know today and on the Columbia crash today is closeup telescopic photos and videos of the actual effects that were taking place on the orbiter.

O'BRIEN: The first job, finding all the pieces that can be found, looking for clues in the fields, forests and backyards of eastern Texas and western Louisiana.

(END VIDEOTAPE)

O'BRIEN: Not many people have experienced investigating this kind of catastrophe, to say the least. Two of our guests this evening do, however. They both investigated the Challenger accident 17 years ago. With me here in Atlanta, Randy Avera, former NASA engineer, and joining us from Boston, Eugene Covert, engineer and educator who served on the presidential commission on the Challenger accident.

Randy, I'd like to begin with you. Let's talk first about this debris, comparing this huge swath of land where debris has been rained down, compare that to the challenge of trying to lift debris off the ocean floor. Which is the greater challenge for the team?

AVERA: Well, both have their own unique challenges, but the large area, land mass today is certainly a different challenge from that of 1986, when the many elements of the Coast Guard, Navy SEALs and U.S. Navy were diving down in about 100 feet or so of the Atlantic Ocean water to retrieve the evidence from the floor of the ocean, as well as collecting it off the surface of the ocean, headed northbound into Gulfstream currents. There are many more people that are able at this point today to find components that are lying on the ground, so it will be something we look back at comparing the two to see which collected the evidence most efficiently.

O'BRIEN: All right, Eugene Covert, would you concur with that? I mean, one of the concerns, of course, is that people will take souvenirs and that that souvenir might very well be the smoking gun?

EUGENE COVERT, CHALLENGER COMMISSION: Well, by and large, I would agree. However, I believe that with the activity on the surface -- the bottom of the ocean, it's possible that the dredges and so forth would cover up bits and pieces that might turn out to be important. I think that the possibility of finding something useful is possibly higher, because it's over land, because there are so many people involved.

Of course, one of the problems may be that somebody is trying to sneak a souvenir away. I understand that's a federal offense and probably you don't want to mess with the feds to do it.

O'BRIEN: Not only that, very hazardous.

Randy, I want to call your attention to something I just found out. I was working the phones here when I had a little break, and if you look at these two flaps, these are movable surfaces on the trailing end of the wing; they're called elevons. It controls the pitch, the up-down motion of the nose, relative to its forward motion. I'm told that prior to those problems with the heat sensors, left wing, this area here, there was some unusual elevon movements, that they're looking at right now, as we speak, poring over the data. What would that tell you?

AVERA: Well, it could tell us one of a couple of things. It could be that that elevon movement was due to commands that were being sent to the elevons from the onboard general purpose computers. If the inertial measurement system of the orbiter, which monitors the attitude of the orbiter and whirl pitch and (UNINTELLIGIBLE), that it was issuing a command or a series of command to drop those elevons into dynamic positions, that would just be a response from a command.

On the other hand, if the hydraulic actuators, which drive the elevons, there are four elevons, two on each wing, and each elevon has a large hydraulic actuator, if those actuators had any malfunctions or failures within the hydraulic actuator, that could also be an issue, but NASA will be separating these into various categories, looking at the data, looking at the flight data and reviewing the design and also service history, repairs or anything that may have been done to those elevon actuators or the actual rigging of the what are called flipper doors. These are metal and composite material panels that are above what we call the wing cove area.

O'BRIEN: All right. I want to get one more point in from Eugene Covert. I'm sorry, Randy, to cut you off, but we're running short on time. Mr. Covert, is there anything that you've seen in all of these briefings that catches your attention more than something else?

COVERT: Well, I'd have to agree about this, one of the worst things you can do is speculate at a time like this. It seems to me that there are enough opportunities to make a mistake and pout your feet in your mouth. Nature provides you the opportunity now not to speculate, and not to -- but to wait, rather, and tell some...

O'BRIEN: All right, but let me ask you this, short of speculating, do you feel fairly confident NASA will come up with a root cause of this?

COVERT: I -- certainly based on my previous experience, I think that the odds are very high that they will come up with a root cause. I think it's important to point out that the reason you have a serious accident investigation of this kind is to find out what went wrong, take those steps to reduce the likelihood of having such an accident again. I think that requires patience on the part of everybody. I can understand why people are impatient. Nevertheless, I think that patience is required. And if you give the investigators the chance to look at stuff coldly, and look at the facts dispassionately and follow the clues to where they will lead you.

O'BRIEN: Eugene Covert, Randy Avera, thank you very much for navigating what are very complex waters for the lay person. We appreciate it.

One of the reasons we explore space is to push the boundaries of science, and for the shuttle Columbia, 16 days in space, it had been entirely devoted to scientific experiments. It's not an exaggeration to say that years of preparation go into the experiments that are selected to fly on space shuttles. But Columbia carried experiments on changes in flame, how flame spread in space, and how flowers change their scent in the absence of gravity. They also studied the effects of weightlessness on rats, to learn more about how weightlessness affects humans long term. They measured atmospheric dust, to see what dust has to do with global warming. That was the principal experiment of Ilan Ramon, the Israeli astronaut. They were bee, ant and spider behavior tests in weightlessness, crystal growth with the hope of finding potential drugs which could cause -- cure things like cancer, even. Tumor development in space was studied, colon cancer, specifically, and there was a study on the evolution of life in the universe that had as its two principal investigators an Israeli and a Palestinian.

Now, along with the crew and shuttle Columbia itself, the knowledge gained on all these experiments vanished today in the skies over Texas.

Send it now -- we're going to take a break; we'll be back with more in just a moment.

(COMMERCIAL BREAK)

WOODRUFF: Flags flying at half-staff over the executive office building right next door to the White House. Earlier today, President Bush remembered Columbia's last crew of seven for their courage, he said, their daring and their idealism. For four of them, this was their first trip into space. Two were colonels; both with the Air Force -- one American, the other Israeli. Ilan Ramon was his country's first astronaut. He joined NASA as a payload specialist in 1997. Married with four children, Ramon was 48 years old.

The commander of this mission was Rick Husband. He had been an astronaut since 1994, and piloted the shuttle Discovery just about four years ago. Husband leaves behind a wife and two children.

Laurel Clark was one of two doctors on this; her first flight. A mission specialist, she was the mother of one.

William McCool was Columbia's pilot. Age 41 and married, he, too, was flying his first mission in space.

David Brown was the other surgeon on board the shuttle, a former college gymnast, a mission specialist for the flight. He was 46 years old.

The payload commander was Michael Anderson. He flew aboard the shuttle Endeavour in 1998. That took him to the Mir Space Station. Anderson was married, and 46 years old.

Kalpana Chawla was a native of India. She became an astronaut in 1994. She operated the shuttle's robotic arm on a mission three years later.

As we remember these astronauts, some of their relatives have chosen to share their grief and their apprehensions with the public. The parents of astronaut David Brown told CNN that they hope the nation's space exploration will go forward, but they said they're also afraid that today's loss was so catastrophic, nothing would be found of the shuttle or of their son.

(BEGIN VIDEO CLIP)

PAUL BROWN, DAVID BROWN'S FATHER: There's nothing left to study. We saw the debris come down in the newsreels, photographs. I'd like to have something of Dave to bury. And may not happen.

(END VIDEO CLIP)

WOODRUFF: So hard.

The sister of astronaut Michael Anderson was still in shock when she talked with reporters.

(BEGIN VIDEO CLIP)

UNIDENTIFIED FEMALE: (UNINTELLIGIBLE) something very definite. Right now, I'm not listening to the TV, because they -- what they said was nothing that I guess I want to believe, because it's nothing that I feel is truly definite yet, so I'm not even listening.

UNIDENTIFIED MALE: I see. What are your plans? Are you planning to go to Dallas any time soon?

UNIDENTIFIED FEMALE: To Houston. Yes. I'll go to Houston when I think it's appropriate. I'll go to Houston to be with my sister-in- law, and if necessary, I will be going to Spokane, Washington.

(END VIDEO CLIP)

WOODRUFF: Her brother, astronaut Michael Anderson, grew up in the Spokane area. He flew to Russia's Mir Space Station in 1998. He was in charge of Columbia's science experiments.

Well, as we've noted, there is an international dimension to today's tragedy. Ilan Ramon, the first Israeli astronaut to fly in space, was on board the shuttle Columbia. His presence was a source of enormous pride for Israelis, and now is the cause of tremendous grief. CNN's Kelly Wallace joins us from Jerusalem -- Kelly.

KELLY WALLACE, CNN CORRESPONDENT: Judy, the first Israeli to travel in space gave his country something to cheer about and celebrate after months and months of violence, but now Israelis are engaged in what has become an all too familiar ritual here, mourning, this time the loss of a national hero. Colonel Ramon had a distinguished military career. He fought for Israeli in two wars. He also took part in the successful bombing of a nuclear reactor being built in Iraq in 1981. His extended family, his father and his brother, are now making their way to the United States, to be reunited with Colonel Ramon's wife and its four children.

Before leaving, Ramon's brother spoke out about the e-mails he had been receiving. He said Ramon looked at this shuttle mission as his proudest accomplishment.

(BEGIN VIDEO CLIP)

ELIEZER WOLFENMAN, ILAN RAMON'S FATHER (through translator): There was euphoria and great joy, because it was the realization of Ilan's greatest dream. He was overjoyed. He corresponded from the shuttle. He wrote that he felt he was above the clouds in every sense.

(END VIDEO CLIP)

WALLACE: And condolences coming in from throughout the world, including the Palestinian community. Yasser Arafat, expressing his condolences to the American people and also to the Israeli people for their loss tonight -- Judy.

WOODRUFF: Thanks, Kelly, a tragedy that brings us all together.

Well, one of the Columbia's astronauts who died this morning was Dr. Laurel Blair Salton Clark. She was a mission specialist. Clark was a U.S. Navy commander and a medical doctor. She considers Racine, Wisconsin her home town, and our Ceci Rodgers is there -- Ceci.

CECI RODGERS, CNN CORRESPONDENT: Hi, Judy. We're in front of Laurel Clark's high school, where people have been gathering all evening to pay respects to a fallen hero.

(BEGIN VIDEOTAPE)

RODGERS (voice-over): On the last day of shuttle Columbia's two- week mission, it was Laurel Clark who took Houston's wake-up call.

(BEGIN VIDEO CLIP)

LAUREL CLARK, MISSION SPECIALIST: Good morning, Houston. We're getting ready for a big day up here. Had a great time on orbit, and really excited to come back.

(END VIDEO CLIP)

RODGERS: That the 41-year-old wife and mother would not make it home is still sinking in in her home town of Racine, Wisconsin. A makeshift memorial sits outside Harlech (ph) high school, where Laurel Salton, as she was known then, is something of a hero.

DANIEL SALTON, DR CLARK'S BROTHER: But she did what she wanted to accomplish. And we all followed the flight and what she was doing up there, and to have something like that and this kind of a tragedy is just almost beyond words to describe.

RODGERS: Students heard the news at a wrestling match, and paused for a moment of silence and to sing the National Anthem.

UNIDENTIFIED FEMALE: She was the greatest role model to us, because it's pretty cool how someone could from our school could go up in space. It's just awesome.

RODGERS: In nearby Milwaukee, Clark's brother said family members take comfort in the fact that she at least fulfilled a lifelong dream to travel in space.

SALTON: She was a person who was very goal-oriented, and that's where she got where she was, but she was so warm and friendly with the people. She loved kids. We all are very concerned about her son Ian (ph) and how he'll pull through this.

RODGERS: Family members also take comfort in her many accomplishments. She had degrees in zoology and medicine from the University of Wisconsin at Madison and worked as a Navy submarine doctor, at one point stationed in Scotland, before going to the space program.

(BEGIN VIDEO CLIP)

CLARK: Hearing that song reminds me of all the different places found on earth and all the friends and family that I have all over the world. Thanks, and it's been great working with you and all the other folks.

(END VIDEO CLIP)

(END VIDEOTAPE)

RODGERS: Her home in Wisconsin was never far from Laurel Clark's thoughts. She took a pennant from her high school up with her in the shuttle, and she was planning to take pictures of a lighthouse not far from here on Lake Michigan that she was supposed to have been able to see from her bedroom at home -- Judy.

WOODRUFF: Ceci Rodgers, taking us to the home town of one of the seven lost today. Miles, it just breaks your heart.

O'BRIEN: It does indeed, Judy.

So once again, the United States is in mourning, this time for seven space explorers, who died today over Texas. CNN's Bruce Morton has more.

(BEGIN VIDEOTAPE)

BRUCE MORTON, CNN CORRESPONDENT (voice-over): Americans mourn in churches.

REV. JERRY SLOVAN: All this week our prayers will be for the families that survived those seven astronauts and the whole space program family.

MORTON: At the Kennedy Space Center, at the White House, flags are at half-staff. At NASA headquarters here, a flag and a banner, which now looks sad. Family members grieve, of course.

UNIDENTIFIED FEMALE: That's what he dreamed of doing most of his life. That's what he said was his goal to do.

MORTON: The principal of astronaut David Brown's old high school.

RAYMOND PASI, HIGH SCHOOL PRINCIPAL: Called us last year and asked if there was something that he could take from the high school up with him on this space mission. We eventually did send him a banner of the school that he brought up.

MORTON: Strangers were shocked, in a gym, in Chicago's planetarium.

UNIDENTIFIED FEMALE: I went to space camp, and (UNINTELLIGIBLE) almost, so (UNINTELLIGIBLE) get into that.

UNIDENTIFIED MALE: I'm feeling pretty bad about this, actually. Ever since Challenger crash, I thought there was never going to be another space shuttle accident.

UNIDENTIFIED FEMALE: Pure shock. This -- this is unreal. I mean, you come out here expecting to see a shuttle land, and it's just not there.

MORTON: In fact, it's just 17 years and three days since the shuttle Challenger exploded on takeoff. On the anniversary, Columbia Commander Rick Husband remembered that crew and three others who died in the 1967 fire.

(BEGIN VIDEO CLIP)

RICK HUSBAND, COMMANDER, COLUMBIA: Their dedication and devotion to the exploration of space was an inspiration to each of us. It still motivates people around the world to achieve great things in service to others.

(END VIDEO CLIP)

MORTON: President Bush led the mourning for the seven who died aboard Columbia.

BUSH: The crew of the shuttle Columbia did not return safely to Earth, yet we can pray that all are safely home. MORTON: And at the NASA briefings for reporters, some voices broke.

BILL READY, NASA: My promise to the crew and to the crew families is that the investigation that we have just launched will find the cause, we'll fix it and then we will move on.

MORTON: They will move on. Humankind has crossed oceans, explored continents, walked on the moon. Some kid tonight will be looking at the stars and thinking, why not? The urge to know what's out there is part of who we are.

Bruce Morton, CNN, Washington.

(END VIDEOTAPE)

O'BRIEN: The exploration, we hope, will continue. Let's turn now to Wolf Blitzer in Houston -- Wolf.

BLITZER: You know, Miles, even as this investigation gets going, and questions about the future of the space missions are asked, all sorts of commissions of inquiry, perhaps, that we're not even envisioning, people here in Houston at the Johnson Space Center, they're coming to the gates of the center, they're dropping off flowers, they're remembering, they're expressing their anguish, their sadness.

Take a look at the picture of these seven astronauts. You look at them, you see the five men, the two women. Of those five men, one African American, one Israeli, the Indian American woman. It's a beautiful mosaic, cut short, so sadly -- Miles.

O'BRIEN: Wolf Blitzer in Houston.

On behalf of Wolf in Houston at the Johnson Space Center and Judy Woodruff in Washington, as well as Lou Dobbs down at the Kennedy Space Center, thank you very much for being with us for this special report. Be sure to join me again for another special report an hour from now, "Columbia Shuttle Tragedy," that's at 10:00 p.m. Eastern, 7:00 Pacific. I'm Miles O'Brien. "LARRY KING LIVE" is up next right here on CNN.

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Aired February 1, 2003 - 20:00   ET
THIS IS A RUSH TRANSCRIPT. THIS COPY MAY NOT BE IN ITS FINAL FORM AND MAY BE UPDATED.
(BEGIN AUDIO CLIP)
UNIDENTIFIED MALE: Columbia, Houston, we see your tire pressure messages and we did not copy your last.

UNIDENTIFIED MALE: Roger ...

(END AUDIO CLIP)

ANNOUNCER: The final moments before a national tragedy. Heading home, shuttle Columbia breaks up in mid-air.

(BEGIN VIDEO CLIP)

GEORGE W. BUSH, PRESIDENT OF THE UNITED STATES: At 9:00 this morning, Mission Control in Houston lost contact with our space shuttle Columbia. A short time later, debris was seen falling from the skies above Texas.

The Columbia is lost. There are no survivors.

(END VIDEO CLIP)

ANNOUNCER: Seven crew members lost. NASA officials begin a daunting investigation.

(BEGIN VIDEO CLIP)

CAPT. BILL READDY, ASTRONAUT, U.S. NAVY (RET.): My promise to the crew and to the crew families is that the investigation that we have just launched will find a cause. We'll fix it. And then we'll move on.

(END VIDEO CLIP)

ANNOUNCER: Tonight, a CNN Special Report -- "Columbia: A Shuttle Tragedy." From the CNN center in Atlanta, here's Miles O'Brien.

MILES O'BRIEN, CNN ANCHOR: Good evening. In the 42 years of U.S. human space flight, there had never been a fatal accident during the decent to earth or in landing. But this morning, that all changed.

Sixteen minutes before it was scheduled to touch down in Florida at the Kennedy Space Center, the space shuttle Columbia fell apart in the skies over Texas. You're looking at some animation developed through the good graces of analytical graphics. And what you see is the general scenario that occurs on re-entry, as the space shuttle returns from space, traveling at some 17,500 miles an hour, breaking its way toward the runway at the Kennedy Space Center on the Florida peninsula -- pitching, nose high up, presenting to the strongest portion of the heat those black tiles, there to insulate the space shuttle, which is, after all, an aluminum frame aircraft, from the 3,000 degree heat of re-entry.

It was at the absolute apex of that heat -- mach 18, 200,000 feet and change -- when the space shuttle Columbia disintegrated high over Texas.

This scenario is being watched very closely in Houston right now. There's a mission evaluation team right now poring over data which was captured immediately after it became apparent that there was a catastrophic failure of the space shuttle Columbia.

I'm told that mission managers will be looking very closely, and the engineers will be looking closely at what happened to the elevons. These are the flaps in the rear portion of the space shuttle Columbia.

There is some indication now, based on the preliminary look at the data, that there was some unusual movement by these elevons -- perhaps something that might have caused an abrupt maneuver -- very early in this investigation. But that is one of the things being looked at as they burn the midnight oil in Houston in the mission evaluation room.

In the morning there will be a series of meetings -- 8:00 a.m. local time, 9:00 a.m., 10:00 a.m. -- series of management meetings and engineering meetings to look at the data preliminarily, get a sense of where they're headed, and then in the noon hour, Central time, they will report back to reporters with another briefing, to give us a better sense of where they're headed with this investigation -- still, obviously, in the very early hours.

Coming up in the next hour of this program, extensive coverage of the Columbia tragedy and what might have gone wrong.

Also anchoring tonight's coverage, Wolf Blitzer live at the Johnson Space Center in Houston, Lou Dobbs from the Kennedy Space Center in Florida, and following the Bush administration's reaction, Judy Woodruff in Washington.

First, let's quickly update you on the very latest. All future space shuttle flights are now on hold until NASA gets a better grip on what went so terribly wrong this morning, as you see in these pictures, breaking up south of Dallas.

Space agency officials say not to worry, though, about crew members still aboard the international space station. They have enough supplies to last until June.

FEMA, the Federal Emergency Management Agency, has been put in charge of recovering and collecting the debris over a tremendously wide swath of the continental United States. The military has been called in to help that search.

They're concentrating on eastern Texas, bits and piece of the shuttle -- pieces of the shuttle -- have also been found in parts of Louisiana.

And, experts say, that because Columbia broke up at 200,000 feet, the debris field could extend to, even into Arkansas, Arizona and New Mexico.

Outside NASA headquarters and at the White House, flags flying at half-staff -- a tribute to the seven astronauts on board the space shuttle Columbia.

Many of the crew's relatives were at the Kennedy Space Center excitedly awaiting the touchdown -- a touchdown which never came -- after a 16-day science mission, which by all accounts was nearly flawless.

This was the 28th mission for the space shuttle Columbia -- focused on science, as we told you -- and Israel's first astronaut in space.

(BEGIN VIDEO TAPE)

UNIDENTIFIED MALE: ... three, two, one. We have booster ignition and liftoff of space shuttle Columbia with a multitude of national and international space research experiments.

O'BRIEN (voice-over): 10:39 a.m., January 16th. Columbia takes off.

UNIDENTIFIED MALE: ... now controlling the flight of Columbia, the international research mission finally underway. Commander Rick Husband joined on the flight deck by pilot Willie McCool, flight engineer Kalpana Chawla and mission specialist Dave Brown. Mission specialist Laurel Clark, payload commander Mike Anderson and payload specialist Ilan Ramon, seated down on the mid-deck.

O'BRIEN: 10:41 a.m. About 80 seconds into the flight, a piece of debris on the external fuel tank comes off, hitting the underside of the orbiter left wing.

There is some concern about overheating during re-entry if enough tiles are knocked loose. But after studying the images frame by frame, NASA engineers decide to continue the mission.

3:10 p.m., January 25 -- one week into the mission. The crew gives CNN an update from space.

RICK HUSBAND, SHUTTLE COMMANDER, SPACE SHUTTLE COLUMBIA: ... up here. We had a great ride to orbit, and all the activation of the experiments in the SPACEHAB went extremely well. And we're really -- we've got our space legs and up and running.

O'BRIEN: Another week passes. Saturday morning, February 1. The crew is just hours from returning home.

LAUREL CLARK, ASTRONAUT, SPACE SHUTTLE COLUMBIA: Good morning, Houston. We're getting ready for a big day up here. Had a great time on orbit. Really excited to come back home.

O'BRIEN: 8:15 a.m., while still in orbit, Columbia fires its breaking rockets. Its touchdown sequence is underway. It begins re- entry.

8:59 a.m. Mission Control hears from Columbia for the last time.

UNIDENTIFIED MALE: And Columbia Houston, we see your tire pressure messages, and we did not copy your last.

UNIDENTIFIED MALE: Roger, ...

O'BRIEN: 9:00 a.m., just 16 minutes away from its scheduled touchdown on Florida's east coast, Mission Control in Houston loses all data and voice contact with Columbia.

The shuttle is seen in the skies above Dallas, Texas. At this point, the spacecraft is roughly 203,000 feet above the earth, traveling about 12,500 miles an hour.

Residents across Texas, Arkansas and Louisiana see what NASA is not yet talking about.

UNIDENTIFIED FEMALE: We were woken up by this rumble. Today we were trying to sleep in on Saturday. And we heard this -- sounded like a train going through our property.

UNIDENTIFIED FEMALE: The dogs started barking and then got shook -- like shook the earth.

UNIDENTIFIED MALE: And we seen large masses of pieces coming off of the shuttle.

UNIDENTIFIED FEMALE: I'm devastated. Devastated. It's unbelievable.

O'BRIEN: And the National Weather Service even picks up these images on radar.

UNIDENTIFIED MALE: That is the wreckage of the shuttle Columbia coming through ...

O'BRIEN: 9:20. Quiet disbelief in the control room in Houston -- and from onlookers at the Kennedy Space Center.

UNIDENTIFIED MALE: We're shocked. We're -- we -- at a loss for words. We don't know what to think. We feel so sad and sorry for the families of people that have been lost. Just hope they're with God.

O'BRIEN: 9:29 a.m. NASA declares an emergency. Calls reporting debris hitting the ground flood police, NASA and newsroom phones.

9:44 a.m. NASA warns residents to stay away from the debris, which could be dangerous, because of toxins in the propellants used.

11:00 a.m. A flag at the Kennedy Space Center next to the countdown clock is lowered to half-staff.

1:30 p.m. NASA Administrator Sean O'Keefe.

SEAN O'KEEFE, NASA ADMINISTRATOR: We trust the prayers of the nation will be with them and with their families.

And, again, a more courageous group of people you could not have hoped to know -- and the families of these crew members.

An extraordinary, extraordinary group of astronauts who gave their lives.

O'BRIEN: 2:05 -- the President addresses the nation, delivering the gravest news.

BUSH: This day has brought terrible news and great sadness to our country.

The Columbia is lost. There are no survivors.

(END VIDEO SEGMENT)

O'BRIEN: At Mission Control in Houston, the first indication of trouble this morning was the loss of temperature sensors on Columbia's left wing, almost as if the plug had been pulled.

This was followed within seconds by a series of other problems. Wolf Blitzer joining us live now from the Johnson Space Center in Houston -- Wolf.

WOLF BLITZER, CNN ANCHOR: Miles, as you well know, this is a small family, all the people involved in this mission control operation here.

And there's tremendous, there's especially severe sadness here, because the seven astronauts had trained here in Houston at the Johnson Space Center. Their families, by and large, were here. They had had spent a long time getting ready for this mission. And everyone here is, as they've said to me, that words can't describe how upset, how sad they are at what's going on.

And spontaneous memorial services are erupting, even outside the gates of the Johnson Space Center here in Houston, Texas.

Now, they are urging the public to try to help if they can. They know there are hundreds, perhaps thousands of pieces of debris out there. They know that the public saw the images of the debris landing in central Texas, northern Texas -- all over here, all the way over to Louisiana.

They are asking, anyone has any film, any video, there's two ways of getting in touch with NASA officials. You can either call them at a number we've been putting up on the screen, 281-483-3388. I'll repeat that, 281-483-3388.

Or, you can e-mail them if you believe you have some information that could help the investigators. Their e-mail address is columbiaimages@nasa.gov.

Columbiaimages -- all one word -- @nasa.gov.

Now, Ed Lavandera has been out there in Texas. He's been talking to people who have seen some of the debris. Ed Lavandera is joining us now live from Nacogdoches.

Ed, tell us what you've seen and what you've heard.

ED LAVANDERA, CNN CORRESPONDENT: Well, Wolf, what we've seen throughout the day is many people -- actually closer to the Dallas- Fort Worth area, many people were paying attention to this shuttle landing today. Just kind of the course of events today, kind of everything lined up nicely.

It was a beautiful day here weather-wise in Texas, and many people were able to see. One of those great moments where you could see the space shuttle streaking across the State of Texas as it was headed toward Florida for its final approach.

And so, a lot of people watching the live coverage on the local newscast, that as the shuttle was streaking overhead here. So that was a very strange moment, not something -- a very unique moment, I should. Not a chance that a lot of people get to see.

So we are about 3.5 hours southeast of the Dallas-Fort Worth hour, and about another three hours north of Houston, to kind of pinpoint you. And we're in the center of Nacogdoches, Texas.

And this has kind of become a nerve center, if you will, for a lot of people who have come here.

And the reason they're here is, this one parking lot, is there's just a three-by-three-foot piece of debris there. And this is very significant of what we've seen throughout the East Texas area.

In people's backyards, driveways, sidewalks, the back roads of East Texas have seen small parts of debris like this scattered all over the place. When we've seen the areas cordoned off just like this, and many times we've often seen private landowners.

They are doing the same -- waiting for authorities to come by and pick up this material. We understand that they're trying to line up the process by how exactly they're going to do this.

I've also had a chance to speak with other people who say that they have seen debris in the back of their businesses and their homes, as well. And that, I guess, there's just so many calls that have been coming into the authorities here in the East Texas area that it's been impossible to get somebody out to all of these locations at this point so far. So there's a lot of work still left to do here, Wolf.

BLITZER: Ed, to people understand, by and large, how dangerous it is, these toxic propellants as they call it. That if anybody gets too close or touches the kind of debris, they could be in trouble?

By and large, has that message gotten through?

LAVANDERA: You know, for the most part I have seen that -- you'll be driving around a neighborhood and you'll see a debris -- a piece of debris on the ground. And what you'll see is a lot of people gathered around, but they'll probably -- they'll keep a safe distance from it, not touching it.

A lot of people taking pictures of it. But for the most part, I think that word has gotten out that people should stay away.

BLITZER: And it is, of course, the property of the United States government. It would be a crime for anyone to take any of that debris with them.

CNN's Ed Lavandera joining us from Nacogdoches in Texas. Thanks very much, Ed.

And, Miles, when I throw it back to you, the -- as you well know, the investigators want to collect as much of that debris as possible. It's unclear whether they're going to try to recreate as best they can the Columbia. But they do want that debris, because there could be some telltale signs of what exactly caused this horrible explosion -- Miles.

O'BRIEN: Well, Wolf, as you well know, it's not an overstatement to say that this thing could be unlocked, the puzzle could be solved by simply one piece.

So, we encourage people, if they see pieces to let NASA know. Who knows what the significance of that piece might be?

We're going to take a short break. And when we return, we're going to go to Washington and check in with Judy Woodruff and talk about the President and the political implications of all this, as NASA embarks on efforts to fly one day again.

And we'll also check in with Lou Dobbs, who is at the Kennedy Space Center, where Columbia left 16 days ago in a blaze of glory.

Stay with us.

(COMMERCIAL BREAK)

O'BRIEN: We all knew it would happen. We just didn't know how.

That's the words of one NASA worker from Houston today, as they consider what happened, as the space shuttle Columbia came in on what seemed like the flawless conclusion to a nearly flawless mission. Let's continue our coverage as we turn our attention now to Washington and to Florida, on a story that really spans the entire country.

Lou Dobbs at the Kennedy Space Center, but first, Judy Woodruff in Washington -- Judy.

JUDY WOODRUFF, CNN ANCHOR: That's right. Thank you, Miles. And it has been a full day, and a very difficult day, for President George W. Bush, who, as we know, until just lately, his main focus has been pressing the U.S. case against Iraq.

Well, today, the President has talked by telephone with the families of the lost astronauts. He has spoken words of consolation to the rest of the country -- to all of us.

CNN's White House correspondent, Suzanne Malveaux, has been at the White House all this day following developments -- Suzanne.

SUZANNE MALVEAUX, CNN WHITE HOUSE CORRESPONDENT: Well, Judy, tonight leaders around the world are offering their condolences to the White House, as President Bush marks this tragic day with reflection, mourning and prayer.

(BEGIN VIDEOTAPE)

MALVEAUX (voice-over): In honor of those lost, the flag at the White House lowered at half-staff. President Bush, once again, charged with ...

WOODRUFF: Testing, one, two, three, testing ...

MALVEAUX: ... carrying out the somber duty ...

WOODRUFF: ... one, two, three, four, five ...

MALVEAUX: ... of bringing the nation together in times of tragedy.

BUSH: My fellow Americans, ...

WOODRUFF: Testing. You want it up higher?

BUSH: ... this day has brought terrible news and great sadness to our country.

WOODRUFF: Testing, one, two, three, four, five.

BUSH: At 9:00 this morning, Mission Control in Houston lost contact with our space shuttle Columbia. A short time later, debris was seen falling from the skies above Texas.

The Columbia is lost. There are no survivors.

MALVEAUX: Six Americans and one Israeli lost -- people the President said assumed great risk in the service to all humanity. BUSH: The cause in which they died will continue. Mankind is led into the darkness beyond our world by the inspiration of discovery and the longing to understand.

Our journey into space will go on.

MALVEAUX: Just after 9:00 this morning at Camp David, President Bush is notified by his chief-of-staff that NASA has lost contact with the shuttle.

At 10:30, he's briefed by NASA's director, and decides to return to the White House early. The situation room at the White House goes into full gear, notifying all the principals.

By 12:30, the president is back in the Oval Office, when NASA's director tells him there are no survivors.

Fifteen minutes later, Mr. Bush, standing at his desk, holds a conference call with the victims' families, who are gathered around a speakerphone at the Kennedy Space Center.

He tells them, "We express our love and appreciation for all those who died today. I want the loved ones to know there are millions of Americans praying for you, including me and Laura.

"It's an incredibly tough day for you. May God bless you all. I wish I was there to hug, cry and comfort you right now."

In a poignant moment, the White House aide who was with the President says after the call, a somber Mr. Bush briefly excused himself to the executive residence.

The president also called Israeli Prime Minister Ariel Sharon, to offer his condolences for the Israeli astronaut lost. And the President received calls from world leaders -- from Mexico, Canada, and even those recently at odds with the president over his stand with Iraq -- France and Russia.

(END VIDEOTAPE)

MALVEAUX: And, Judy, today was a big day for the Department of Homeland Security, as new Secretary, Governor Tom Ridge, able to quickly assess and gather information, assigned FEMA the lead role in recovery, and also to reassure the American people, that as tragic as this disaster was, it was not the result of terrorism -- Judy.

WOODRUFF: All right. Thank you, Suzanne.

At the same time, they are saying they are pressing ahead with the case against Iraq. That will continue.

Well, as you've been hearing from my colleague, Miles O'Brien, NASA's engineers are already hard at work trying to solve the mystery of what happened to the shuttle Columbia.

But a number of other federal agencies are also involved in the investigation. And for that part of the story, we're going to bring in our Patty Davis -- Patty.

PATTY DAVIS, CNN CORRESPONDENT: Well, Judy, FEMA is heading the response and recovery effort. Other agencies are heading south to take part in the investigation.

(BEGIN VIDEOTAPE)

DAVIS (voice-over): The debris strewn across several states is crucial of finding what caused the accident.

RON DITTEMORE, NASA SHUTTLE PROGRAM MANAGER: We are going to gather every piece we can find, treat this much like an aircraft incident, and see if we can solve the puzzle.

DAVIS: Finding the pieces is a massive undertaking, but an essential one.

If the cause is structural, debris could provide the key clues.

GUY GARDNER, FORMER SHUTTLE ASTRONAUT: They can then piece that together to figure out how it came apart. And then that'll help them figure out where the cause was.

DAVIS: That's why officials are appealing to the public to turn over any pictures people took of the shuttle falling, and to turn in any pieces found.

GOV. RICK PERRY, TEXAS: If you find debris, please call local authorities immediately to tell them of the location.

DAVIS: The Federal Emergency Management Agency is coordinating the federal government's response and recovery. The military guarding and searching for debris using planes, boats and helicopters.

The FAA instituting a 40-mile-wide, 160-mile-long restricted zone below 3,000 feet from Texas to Louisiana, to protect aircraft involved in the recovery.

The National Transportation Safety Board sending vehicle structure and system experts to help.

NTSB crash investigators helped piece together debris from the in-flight of the TWA 800 crash. This debris field as much as 100 times bigger.

PETER GOELZ, FORMER MANAGING DIRECTOR, NATIONAL TRANSPORTATION SAFETY BOARD: This is going to be an extraordinarily challenging investigation. The vehicle was at 200,000 feet. It was traveling at 12,500 miles per hour.

There certainly has never been a breakup by -- like this in aviation or space history.

DAVIS: In addition to debris, NASA says the shuttle had data and voice recorders. But more importantly, it was constantly streaming information to mission control. DITTEMORE: We are preserving hardware around the country in our different facilities. We are impounding data here that represented the last data that we received from the crew.

And we will be poring over that data 24 hours a day.

(END VIDEOTAPE)

DAVIS: Besides NASA's own investigation, an independent group, including the military, the FAA will also look into what happened -- an investigation that could take months, if not years -- Judy.

WOODRUFF: All right. Patty Davis, thanks very much. When you think about it, Miles, it seems almost a miracle that any pieces survived from that altitude and at that speed.

O'BRIEN: Judy, what I've seen is, there aren't many very big pieces. That is for sure.

Just 12 hours ago, hundreds of people were gathering at the Kennedy Space Center to see the shuttle landing. Their excitement quickly turned to shock.

CNN's Lou Dobbs is at Kennedy -- Lou.

LOU DOBBS, CNN ANCHOR: Miles, as you say, shock. And the shock is still being felt profoundly here by everyone who works at NASA, and who works with NASA.

The NASA administrator, Sean O'Keefe, has spent much of the day comforting the families of the seven astronauts who lost their lives today aboard Columbia.

He has also spent much of his time learning as much as possible about what the NASA engineers and managers and investigators know to this point. And he has been briefing congressional leaders, amongst them House Majority Leader Tom DeLay and Congressman Dave Weldon.

And I want to turn now, if I may, to John Zarrella, my colleague here who has covered the space program for some time.

This represents something of a departure, does it not. Sean O'Keefe has really opened up a process and is sharing information, which has not always been the first reflex at this agency.

JOHN ZARRELLA, CNN CORRESPONDENT: Right, exactly. And certainly back in 1986, that really was not the case back in 1986. It was far more of a closed family here, and they kept the information very close to the vest for quite some time.

But an open process here certainly.

DOBBS: John, I've just been told that our colleague, Gary Tuchman is available. Gary, let's go to you quickly.

GARY TUCHMAN, CNN CORRESPONDENT: ... happened today. We come to you from the Sunrise Diner in Cocoa Beach, just south of the Cape, where people are obviously talking about what happened today.

Right here we have Mike and Joanna.

Mike, you were telling me that Joanna, who is your friend, called you to tell you about the shuttle explosion. What did you think when you first heard it?

MIKE: At first I didn't believe it, you know. Shock and amazement. And then when I seen it was true, you think about the families and all that.

A very sad thing.

TUCHMAN: You tell me, when you live here, you just take for granted that the missions will all go OK.

MIKE: Yes, I mean, when I first moved down here, it was, oh, we had to watch every one come in. And then you just take for granted that they'll get here safely. And this time they didn't.

TUCHMAN: Thanks for talking with us.

We want to go over here. This is Frank and Marilyn. Frank and Marilyn live in New York State half the year, and they live here half the year.

And Marilyn was telling me that regularly, they go out on their balcony, on the ocean here, when the shuttle takes off and when it lands, right.

MARILYN: That's right. It's very exciting. And being away from this area, I don't take it for granted. I think it's so exciting to watch the shuttles when the rockets go up.

And we're on our balcony every single time.

TUCHMAN: Including this morning, right?

MARILYN: Including this morning. We were there ...

TUCHMAN: Tell me what happened this morning.

MARILYN: We were there at 9 o'clock, and I was looking out, looking at some people at the beach, and waiting for the sound of that beautiful -- I'm just really sad about this whole thing.

But I just -- my heart goes out to all of the people involved, the families especially, their children. And Israel -- I feel very sadly, because they have a hero. And India. And especially the United States.

I just -- I'm so sad for all of them. I think they're all heroes.

TUCHMAN: Frank and Marilyn, thank you very much for talking with me. It's obviously very emotional for then nation, for the world, but particularly for the people here on the space coast of Florida.

Lou, back to you.

DOBBS: Gary, thank you very much. Gary Tuchman in Coco Beach, Florida. Now, back to you, Miles.

O'BRIEN: All right. Thank you very much, Lou.

A check of the latest developments in today's shuttle tragedy is just ahead.

And the question burning on so many minds tonight. What went wrong up there?

We'll have a closer look at what we know at this time, obviously very early, and where authorities are focusing their attention as they work through the night tonight at Mission Control in Houston.

Plus, one of the crew members -- Israel's first astronaut. We'll have a live report from Jerusalem for a man who is -- was -- a national hero in that country.

And later, in their own words, family members who were expecting their loved ones to return home to earth this morning. Their thoughts and their feelings on this terribly tragic day.

(COMMERCIAL BREAK)

O'BRIEN: Welcome back. Investigators from the National Transportation Safety Board, NASA, the military and other federal agencies are trying to determine why the space shuttle Columbia broke apart this morning in the sky over Texas. All seven astronauts aboard were lost.

Columbia was at an altitude of some 39 miles, traveling 12,500 miles an hour when it broke into fiery pieces. It was absolutely the hottest point of re-entry, 3,000 degrees Fahrenheit. Parts of the shuttle have been found in east Texas and Louisiana. Some pieces were so hot that they caused fires, as you see here. The spacecraft was so high the debris field may extend into New Mexico and Arizona. Parts of what authorities suspect are human remains also have been found.

Now, as for the cause, several minutes before the breakup, there were some sensors on Columbia's left wing. They began failing, temperature sensors, specifically, toward the rear portion of the wing. Others registered high temperatures, and there are reports that there was some unusual movements of the flaps at the back called ailerons.

Memories have gone back to launch day, where cameras saw a piece of foam insulation from the fuel tank breaking off, hitting Columbia's left wing. The shuttle program manager, Ron Dittemore, says at this point not a smoking gun, but he adds, we cannot discount that there may be a connection.

And we should tell you, the person who will be heading this investigation. NASA has named a retired admiral who also headed the investigation into the explosion aboard the USS Cole in Yemen to lead the investigation. His name is Admiral Harold Gehman, and he will lead this independent investigation into determining the cause of the disintegration of the space shuttle Columbia. We will keep you posted on that.

A team of experts from the National Transportation Safety Board is heading for Barksdale Air Force base in Louisiana. That's where NASA has set up a command post. The NTSB will help the space agency in what is expected to be a lengthy and difficult investigation of this morning's disaster.

(BEGIN VIDEOTAPE)

O'BRIEN (voice-over): First things first. NASA starts eliminating possible causes.

SEAN O'KEEFE, NASA ADMINISTRATOR: We have no indications that the mishap was caused by anything or anyone on the ground.

O'BRIEN: From there, the potential causes are innumerable, given the one million parts and complex operations that go into any shuttle mission.

As rocket scientists like to say, it's always what you do not expect, because if you'd thought of it, you'd have fixed it.

One of the space shuttle program's greatest achievements was the development of the insulating tiles that protect the shuttle on re- entry. There are more than 20,000 of them on each shuttle, made of silicon fiber, they're cool to the touch just seconds after being exposed to a 2,200 degree kiln. While they have been a great achievement, they have been a continuing problem for shuttle managers. They're brittle and can easily be knocked off during launch. The shuttle can land if some insulating tiles are damaged or break off, as seen here on the space shuttle Discovery, but if too many tiles are gone, the shuttle would get too hot.

RANDY AVERA, FORMER NASA ENGINEER: The heat could actually cause the structure of the orbiter to break.

O'BRIEN: During Columbia's launch, a piece of insulation from the external fuel tank broke off and perhaps damaged some ceramic tiles, but shuttle managers determined it was safe for the mission to continue.

RON DITTEMORE, SHUTTLE PROGRAM MANAGER: We can't discount that there might be a connection. But we have to caution you and ourselves that we can't rush to judgment on it.

O'BRIEN: Another likely point of focus for investigators -- the altitude of the shuttle on re-entry. If the nose goes too high or too low, the shuttle could tumble and break up.

UNIDENTIFIED MALE: The belly of the shuttle is well protected, but if you get into wrong orientation at any moment during that re- entry, you are not protected on all sides, and so, you know, once you start coming apart, there is nothing you can do.

O'BRIEN: Columbia was the oldest shuttle. Just last year, engineers found stress and age cracks in shuttle's engine parts. While those problems, experts say, are not likely to be the cause of this disaster, there could be some other unforeseen, age-related problem with the shuttle. Whatever the cause, there may be clues in the data transmitted from the shuttle before communication was lost.

DITTEMORE: We will be poring over that data 24 hours a day fro the foreseeable future.

O'BRIEN: NASA has undertaken major investigations several times before; the last after the Challenger disaster.

Randy Avera worked on that investigation into why the Challenger disintegrated over the ocean shortly after liftoff.

AVERA: What we do not have as far as we know today and on the Columbia crash today is closeup telescopic photos and videos of the actual effects that were taking place on the orbiter.

O'BRIEN: The first job, finding all the pieces that can be found, looking for clues in the fields, forests and backyards of eastern Texas and western Louisiana.

(END VIDEOTAPE)

O'BRIEN: Not many people have experienced investigating this kind of catastrophe, to say the least. Two of our guests this evening do, however. They both investigated the Challenger accident 17 years ago. With me here in Atlanta, Randy Avera, former NASA engineer, and joining us from Boston, Eugene Covert, engineer and educator who served on the presidential commission on the Challenger accident.

Randy, I'd like to begin with you. Let's talk first about this debris, comparing this huge swath of land where debris has been rained down, compare that to the challenge of trying to lift debris off the ocean floor. Which is the greater challenge for the team?

AVERA: Well, both have their own unique challenges, but the large area, land mass today is certainly a different challenge from that of 1986, when the many elements of the Coast Guard, Navy SEALs and U.S. Navy were diving down in about 100 feet or so of the Atlantic Ocean water to retrieve the evidence from the floor of the ocean, as well as collecting it off the surface of the ocean, headed northbound into Gulfstream currents. There are many more people that are able at this point today to find components that are lying on the ground, so it will be something we look back at comparing the two to see which collected the evidence most efficiently.

O'BRIEN: All right, Eugene Covert, would you concur with that? I mean, one of the concerns, of course, is that people will take souvenirs and that that souvenir might very well be the smoking gun?

EUGENE COVERT, CHALLENGER COMMISSION: Well, by and large, I would agree. However, I believe that with the activity on the surface -- the bottom of the ocean, it's possible that the dredges and so forth would cover up bits and pieces that might turn out to be important. I think that the possibility of finding something useful is possibly higher, because it's over land, because there are so many people involved.

Of course, one of the problems may be that somebody is trying to sneak a souvenir away. I understand that's a federal offense and probably you don't want to mess with the feds to do it.

O'BRIEN: Not only that, very hazardous.

Randy, I want to call your attention to something I just found out. I was working the phones here when I had a little break, and if you look at these two flaps, these are movable surfaces on the trailing end of the wing; they're called elevons. It controls the pitch, the up-down motion of the nose, relative to its forward motion. I'm told that prior to those problems with the heat sensors, left wing, this area here, there was some unusual elevon movements, that they're looking at right now, as we speak, poring over the data. What would that tell you?

AVERA: Well, it could tell us one of a couple of things. It could be that that elevon movement was due to commands that were being sent to the elevons from the onboard general purpose computers. If the inertial measurement system of the orbiter, which monitors the attitude of the orbiter and whirl pitch and (UNINTELLIGIBLE), that it was issuing a command or a series of command to drop those elevons into dynamic positions, that would just be a response from a command.

On the other hand, if the hydraulic actuators, which drive the elevons, there are four elevons, two on each wing, and each elevon has a large hydraulic actuator, if those actuators had any malfunctions or failures within the hydraulic actuator, that could also be an issue, but NASA will be separating these into various categories, looking at the data, looking at the flight data and reviewing the design and also service history, repairs or anything that may have been done to those elevon actuators or the actual rigging of the what are called flipper doors. These are metal and composite material panels that are above what we call the wing cove area.

O'BRIEN: All right. I want to get one more point in from Eugene Covert. I'm sorry, Randy, to cut you off, but we're running short on time. Mr. Covert, is there anything that you've seen in all of these briefings that catches your attention more than something else?

COVERT: Well, I'd have to agree about this, one of the worst things you can do is speculate at a time like this. It seems to me that there are enough opportunities to make a mistake and pout your feet in your mouth. Nature provides you the opportunity now not to speculate, and not to -- but to wait, rather, and tell some...

O'BRIEN: All right, but let me ask you this, short of speculating, do you feel fairly confident NASA will come up with a root cause of this?

COVERT: I -- certainly based on my previous experience, I think that the odds are very high that they will come up with a root cause. I think it's important to point out that the reason you have a serious accident investigation of this kind is to find out what went wrong, take those steps to reduce the likelihood of having such an accident again. I think that requires patience on the part of everybody. I can understand why people are impatient. Nevertheless, I think that patience is required. And if you give the investigators the chance to look at stuff coldly, and look at the facts dispassionately and follow the clues to where they will lead you.

O'BRIEN: Eugene Covert, Randy Avera, thank you very much for navigating what are very complex waters for the lay person. We appreciate it.

One of the reasons we explore space is to push the boundaries of science, and for the shuttle Columbia, 16 days in space, it had been entirely devoted to scientific experiments. It's not an exaggeration to say that years of preparation go into the experiments that are selected to fly on space shuttles. But Columbia carried experiments on changes in flame, how flame spread in space, and how flowers change their scent in the absence of gravity. They also studied the effects of weightlessness on rats, to learn more about how weightlessness affects humans long term. They measured atmospheric dust, to see what dust has to do with global warming. That was the principal experiment of Ilan Ramon, the Israeli astronaut. They were bee, ant and spider behavior tests in weightlessness, crystal growth with the hope of finding potential drugs which could cause -- cure things like cancer, even. Tumor development in space was studied, colon cancer, specifically, and there was a study on the evolution of life in the universe that had as its two principal investigators an Israeli and a Palestinian.

Now, along with the crew and shuttle Columbia itself, the knowledge gained on all these experiments vanished today in the skies over Texas.

Send it now -- we're going to take a break; we'll be back with more in just a moment.

(COMMERCIAL BREAK)

WOODRUFF: Flags flying at half-staff over the executive office building right next door to the White House. Earlier today, President Bush remembered Columbia's last crew of seven for their courage, he said, their daring and their idealism. For four of them, this was their first trip into space. Two were colonels; both with the Air Force -- one American, the other Israeli. Ilan Ramon was his country's first astronaut. He joined NASA as a payload specialist in 1997. Married with four children, Ramon was 48 years old.

The commander of this mission was Rick Husband. He had been an astronaut since 1994, and piloted the shuttle Discovery just about four years ago. Husband leaves behind a wife and two children.

Laurel Clark was one of two doctors on this; her first flight. A mission specialist, she was the mother of one.

William McCool was Columbia's pilot. Age 41 and married, he, too, was flying his first mission in space.

David Brown was the other surgeon on board the shuttle, a former college gymnast, a mission specialist for the flight. He was 46 years old.

The payload commander was Michael Anderson. He flew aboard the shuttle Endeavour in 1998. That took him to the Mir Space Station. Anderson was married, and 46 years old.

Kalpana Chawla was a native of India. She became an astronaut in 1994. She operated the shuttle's robotic arm on a mission three years later.

As we remember these astronauts, some of their relatives have chosen to share their grief and their apprehensions with the public. The parents of astronaut David Brown told CNN that they hope the nation's space exploration will go forward, but they said they're also afraid that today's loss was so catastrophic, nothing would be found of the shuttle or of their son.

(BEGIN VIDEO CLIP)

PAUL BROWN, DAVID BROWN'S FATHER: There's nothing left to study. We saw the debris come down in the newsreels, photographs. I'd like to have something of Dave to bury. And may not happen.

(END VIDEO CLIP)

WOODRUFF: So hard.

The sister of astronaut Michael Anderson was still in shock when she talked with reporters.

(BEGIN VIDEO CLIP)

UNIDENTIFIED FEMALE: (UNINTELLIGIBLE) something very definite. Right now, I'm not listening to the TV, because they -- what they said was nothing that I guess I want to believe, because it's nothing that I feel is truly definite yet, so I'm not even listening.

UNIDENTIFIED MALE: I see. What are your plans? Are you planning to go to Dallas any time soon?

UNIDENTIFIED FEMALE: To Houston. Yes. I'll go to Houston when I think it's appropriate. I'll go to Houston to be with my sister-in- law, and if necessary, I will be going to Spokane, Washington.

(END VIDEO CLIP)

WOODRUFF: Her brother, astronaut Michael Anderson, grew up in the Spokane area. He flew to Russia's Mir Space Station in 1998. He was in charge of Columbia's science experiments.

Well, as we've noted, there is an international dimension to today's tragedy. Ilan Ramon, the first Israeli astronaut to fly in space, was on board the shuttle Columbia. His presence was a source of enormous pride for Israelis, and now is the cause of tremendous grief. CNN's Kelly Wallace joins us from Jerusalem -- Kelly.

KELLY WALLACE, CNN CORRESPONDENT: Judy, the first Israeli to travel in space gave his country something to cheer about and celebrate after months and months of violence, but now Israelis are engaged in what has become an all too familiar ritual here, mourning, this time the loss of a national hero. Colonel Ramon had a distinguished military career. He fought for Israeli in two wars. He also took part in the successful bombing of a nuclear reactor being built in Iraq in 1981. His extended family, his father and his brother, are now making their way to the United States, to be reunited with Colonel Ramon's wife and its four children.

Before leaving, Ramon's brother spoke out about the e-mails he had been receiving. He said Ramon looked at this shuttle mission as his proudest accomplishment.

(BEGIN VIDEO CLIP)

ELIEZER WOLFENMAN, ILAN RAMON'S FATHER (through translator): There was euphoria and great joy, because it was the realization of Ilan's greatest dream. He was overjoyed. He corresponded from the shuttle. He wrote that he felt he was above the clouds in every sense.

(END VIDEO CLIP)

WALLACE: And condolences coming in from throughout the world, including the Palestinian community. Yasser Arafat, expressing his condolences to the American people and also to the Israeli people for their loss tonight -- Judy.

WOODRUFF: Thanks, Kelly, a tragedy that brings us all together.

Well, one of the Columbia's astronauts who died this morning was Dr. Laurel Blair Salton Clark. She was a mission specialist. Clark was a U.S. Navy commander and a medical doctor. She considers Racine, Wisconsin her home town, and our Ceci Rodgers is there -- Ceci.

CECI RODGERS, CNN CORRESPONDENT: Hi, Judy. We're in front of Laurel Clark's high school, where people have been gathering all evening to pay respects to a fallen hero.

(BEGIN VIDEOTAPE)

RODGERS (voice-over): On the last day of shuttle Columbia's two- week mission, it was Laurel Clark who took Houston's wake-up call.

(BEGIN VIDEO CLIP)

LAUREL CLARK, MISSION SPECIALIST: Good morning, Houston. We're getting ready for a big day up here. Had a great time on orbit, and really excited to come back.

(END VIDEO CLIP)

RODGERS: That the 41-year-old wife and mother would not make it home is still sinking in in her home town of Racine, Wisconsin. A makeshift memorial sits outside Harlech (ph) high school, where Laurel Salton, as she was known then, is something of a hero.

DANIEL SALTON, DR CLARK'S BROTHER: But she did what she wanted to accomplish. And we all followed the flight and what she was doing up there, and to have something like that and this kind of a tragedy is just almost beyond words to describe.

RODGERS: Students heard the news at a wrestling match, and paused for a moment of silence and to sing the National Anthem.

UNIDENTIFIED FEMALE: She was the greatest role model to us, because it's pretty cool how someone could from our school could go up in space. It's just awesome.

RODGERS: In nearby Milwaukee, Clark's brother said family members take comfort in the fact that she at least fulfilled a lifelong dream to travel in space.

SALTON: She was a person who was very goal-oriented, and that's where she got where she was, but she was so warm and friendly with the people. She loved kids. We all are very concerned about her son Ian (ph) and how he'll pull through this.

RODGERS: Family members also take comfort in her many accomplishments. She had degrees in zoology and medicine from the University of Wisconsin at Madison and worked as a Navy submarine doctor, at one point stationed in Scotland, before going to the space program.

(BEGIN VIDEO CLIP)

CLARK: Hearing that song reminds me of all the different places found on earth and all the friends and family that I have all over the world. Thanks, and it's been great working with you and all the other folks.

(END VIDEO CLIP)

(END VIDEOTAPE)

RODGERS: Her home in Wisconsin was never far from Laurel Clark's thoughts. She took a pennant from her high school up with her in the shuttle, and she was planning to take pictures of a lighthouse not far from here on Lake Michigan that she was supposed to have been able to see from her bedroom at home -- Judy.

WOODRUFF: Ceci Rodgers, taking us to the home town of one of the seven lost today. Miles, it just breaks your heart.

O'BRIEN: It does indeed, Judy.

So once again, the United States is in mourning, this time for seven space explorers, who died today over Texas. CNN's Bruce Morton has more.

(BEGIN VIDEOTAPE)

BRUCE MORTON, CNN CORRESPONDENT (voice-over): Americans mourn in churches.

REV. JERRY SLOVAN: All this week our prayers will be for the families that survived those seven astronauts and the whole space program family.

MORTON: At the Kennedy Space Center, at the White House, flags are at half-staff. At NASA headquarters here, a flag and a banner, which now looks sad. Family members grieve, of course.

UNIDENTIFIED FEMALE: That's what he dreamed of doing most of his life. That's what he said was his goal to do.

MORTON: The principal of astronaut David Brown's old high school.

RAYMOND PASI, HIGH SCHOOL PRINCIPAL: Called us last year and asked if there was something that he could take from the high school up with him on this space mission. We eventually did send him a banner of the school that he brought up.

MORTON: Strangers were shocked, in a gym, in Chicago's planetarium.

UNIDENTIFIED FEMALE: I went to space camp, and (UNINTELLIGIBLE) almost, so (UNINTELLIGIBLE) get into that.

UNIDENTIFIED MALE: I'm feeling pretty bad about this, actually. Ever since Challenger crash, I thought there was never going to be another space shuttle accident.

UNIDENTIFIED FEMALE: Pure shock. This -- this is unreal. I mean, you come out here expecting to see a shuttle land, and it's just not there.

MORTON: In fact, it's just 17 years and three days since the shuttle Challenger exploded on takeoff. On the anniversary, Columbia Commander Rick Husband remembered that crew and three others who died in the 1967 fire.

(BEGIN VIDEO CLIP)

RICK HUSBAND, COMMANDER, COLUMBIA: Their dedication and devotion to the exploration of space was an inspiration to each of us. It still motivates people around the world to achieve great things in service to others.

(END VIDEO CLIP)

MORTON: President Bush led the mourning for the seven who died aboard Columbia.

BUSH: The crew of the shuttle Columbia did not return safely to Earth, yet we can pray that all are safely home. MORTON: And at the NASA briefings for reporters, some voices broke.

BILL READY, NASA: My promise to the crew and to the crew families is that the investigation that we have just launched will find the cause, we'll fix it and then we will move on.

MORTON: They will move on. Humankind has crossed oceans, explored continents, walked on the moon. Some kid tonight will be looking at the stars and thinking, why not? The urge to know what's out there is part of who we are.

Bruce Morton, CNN, Washington.

(END VIDEOTAPE)

O'BRIEN: The exploration, we hope, will continue. Let's turn now to Wolf Blitzer in Houston -- Wolf.

BLITZER: You know, Miles, even as this investigation gets going, and questions about the future of the space missions are asked, all sorts of commissions of inquiry, perhaps, that we're not even envisioning, people here in Houston at the Johnson Space Center, they're coming to the gates of the center, they're dropping off flowers, they're remembering, they're expressing their anguish, their sadness.

Take a look at the picture of these seven astronauts. You look at them, you see the five men, the two women. Of those five men, one African American, one Israeli, the Indian American woman. It's a beautiful mosaic, cut short, so sadly -- Miles.

O'BRIEN: Wolf Blitzer in Houston.

On behalf of Wolf in Houston at the Johnson Space Center and Judy Woodruff in Washington, as well as Lou Dobbs down at the Kennedy Space Center, thank you very much for being with us for this special report. Be sure to join me again for another special report an hour from now, "Columbia Shuttle Tragedy," that's at 10:00 p.m. Eastern, 7:00 Pacific. I'm Miles O'Brien. "LARRY KING LIVE" is up next right here on CNN.

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