As some might reckon it, the beginning of the end for NASA's space shuttle program came 10 years ago Friday, at 8:48:39 a.m. EST on Saturday, Feb. 1, 2003.

The STS-107 crew. Credit: NASA

That's when strain gauge V12G9921A, a sensor in the shuttle Columbia's left wing, began registering a small but unusual increase in stress as the spaceplane descended from orbit to close out its 28th mission. Twenty seconds later, a temperature sensor followed suit.

Over the next few minutes, a shuttle data recorder captured a cascade of alarming sensor readings and failures on the left side of the spacecraft that clearly indicated a rapidly unfolding catastrophe.

It played out in a brutal rush. Just 10 minutes and 53 seconds after that initial strain gauge reading, as the shuttle streaked across the heartland of America, commander Rick Husband was cut off in mid transmission, presumably when the spaceplane veered out of control at Mach 18, breaking apart less than a minute later.

It was 9:59:32 a.m. It would take another two-and-a-half minutes or so for the harsh reality of Columbia's demise to reach the Kennedy Space Center where family members, NASA managers, the ground support team, reporters and photographers were standing by for the shuttle's homecoming.

I was covering Columbia's re-entry from the CBS News bureau at the Florida spaceport, polishing up a post-landing mission wrap-up story that I planned to post to the web within a few minutes of touchdown.

Listening to NASA television in Florida, I had no idea the shuttle was in trouble. I had heard Husband's interrupted transmission, but air-to-ground drop outs were not unexpected during shuttle entries. Still, this one seemed to be lasting longer than usual and I was beginning to feel a bit anxious.

Then, at 9:02 a.m., Justin Ray, a reporter with Spaceflight Now, forwarded an instant message from Stephen Clark, a space enthusiast (now veteran space reporter) who was watching Columbia fly overhead southeast of Dallas.

I will never forget that message and the sudden chill that settled over me as I read it:

Clark: O M G!!!!!!!!!!!!!!!

Clark: DUDE OMG

Clark: It broke up!

Clark: The shuttle broke up!

Ray: He's in Texas

Harwood: What!!!

Harwood: Are you serious?

Ray: Yes

Ray: North of Houston

For a moment, I couldn't move. Clark was a veteran shuttle watcher and I did not doubt his observation. I simply stared at the computer screen for a few seconds, coming to grips with what those words meant, thinking of Husband and his crew, wondering if they were still alive but fearing the worst.

As it turned out, the astronauts almost certainly were already dead, killed by rapid decompression when the crew module broke away from the fuselage and disintegrated high above central Texas.

Over the days, weeks and months that followed, the Columbia Accident Investigation Board uncovered a now-familiar history of external tank foam insulation problems, management miscues and poor internal communications that contributed to the mishap.

As we would learn during the course of the investigation, Columbia sustained its fatal wound 16 days earlier when a briefcase-size chunk of foam insulation fell away from a so-called bi-pod ramp on ship's external tank 81.7 seconds after liftoff.

The lightweight foam slowed rapidly in the supersonic flow and the shuttle, racing skyward at more than 1,500 mph at that point, ran into it at a relative velocity of about 545 mph. The impact blasted a large hole, possibly 6 inches across or wider, in one of the protective heat shield panels making up the left wing's leading edge.

The reinforced carbon carbon making up the shuttle's nose cap and wing leading edge panels experiences the most extreme heating during re-entry, some 3,000 degrees Fahrenheit during the 15-minute zone of "peak heating" just after the orbiter falls back into the discernible atmosphere.

Put simply, the gaping hole in Columbia's wing was not survivable. From that perspective, the beginning of the end was the foam strike and not its inevitable consequence.

But some believe Columbia's crew could, in fact, have been saved if NASA management had recognized the severity of the problem soon enough to mount an emergency rescue flight.

Mission control at the Johnson Space Center at roughly the time Columbia should have landed at the Kennedy Space Center. Numbers on the left screen are followed by an S, indicating a static display. The numbers stopped updating 15 minutes earlier when the shuttle veered out of control above central Texas. Credit: NASA

Engineers analyzing launch photography clearly saw the foam fall from the tank. But they could not see where it struck. From the tracking camera's perspective, the debris disappeared below the left wing and emerged as a cloud of white powder. There was no question it had hit the wing. The question was where? And how much damage had it caused?

A few alarmed shuttle engineers lobbied NASA management to ask the Air Force or the National Reconnaissance Office to aim a spy satellite at the shuttle for a detailed photo inspection. But NASA managers in Florida and Texas rebuffed those efforts and settled instead for an in-house analysis based on computer modeling and past experience.

The engineers assigned the task ultimately concluded the foam strike did not represent a "safety of flight" issue. NASA's Mission Management Team, while concerned about what repairs or modifications might be required for downstream external tanks, dismissed the incident as a concern for Columbia.

And besides, the common wisdom went, without a robot arm and some kind of repair kit, there were no viable options to repair serious heat shield damage. As MMT Chairman Linda Ham famously said at one point, "it's not really a factor during the flight because there is not much we can do about it."

Columbia Space Shuttle debris lies on the floor of the RLV Hangar at Kennedy Space Center, Florida. Credit: NASA

Ham later came under intense criticism during the course of the accident investigation for her quick, seemingly uncritical acceptance of the foam strike analysis.

But Ham did not act in a vacuum and there were many engineers and managers up and down the chain of command who had an opportunity to lodge an objection. While concerns were raised in some quarters, no one stood up and publicly challenged the conclusions of the engineering analysis.

And by that point, as a NASA's analysis would later show, there was nothing Ham or the MMT could have done to save the crew.

While it was theoretically possible to launch the shuttle Atlantis on a rescue mission, it would have required an almost instant awareness of the severity of the problem with Columbia, a decision to commit a second shuttle to flight before the cause of the first failure was known and a willingness to cut corners to get Atlantis off the ground before Columbia ran out of power and air.

And even then, it would have required an enormous amount of luck, with no delays due to technical snags or even bad weather.

But it was theoretically possible, and many within the program regret to this day that NASA did not at least make an attempt. I don't believe it had any realistic chance of success, but as others have said before me, not even trying guaranteed it.

In any case, focusing on the MMT misses the mark. The underlying problem was NASA management's misunderstanding of the severity of the general threat posed by the external tank's insulation.

And they had plenty of warning.

As the Columbia investigation documented, every shuttle flight included foam hits to the orbiter's heat shield even though the agency had a clear-cut rule in place forbidding debris strikes. The rule was never strictly enforced and NASA eventually came to look at foam shedding as an "acceptable risk."

In this frame from a tracking camera, a briefcase-sized piece of foam debris has struck the underside of Columbia's left wing, shattering into a cloud of white particles visible exiting below the wing. Credit: NASA

But concern about the foam ramped up in October 2002, just two flights before Columbia's, when a piece of insulation the size of a mailbox broke away from the shuttle Atlantis' external tank seconds after liftoff. The debris slammed into insulation covering an attachment ring at the base of a solid-fuel booster leaving a crater 4 inches wide and 3 inches deep.

It was a close call. The foam struck just six inches away from a critical electronics box used to relay commands to the booster from the shuttle's flight computers.

Engineers quickly traced the missing foam to one of two bi-pod ramps where insulation was built up around the bases of two struts used to hold the nose of the orbiter to the tank.

On Oct. 31, 2002, NASA managers met at the Kennedy Space Center for a flight readiness review to discuss the shuttle Endeavour's planned launch on the next space station assembly mission. Attended by senior managers and engineers, the FRR was a formal assessment of the shuttle's ground processing, mission planning and any technical issues that required resolution before proceeding with launch.

The foam loss during Atlantis' launch earlier that October was just one of several technical issues on the table and the chairman of the meeting, Bill Readdy, a former shuttle commander serving as NASA's associate administrator for space flight, cautioned everyone to be vigilant.

But during the subsequent discussion, tank managers and engineers argued that problems with Endeavour's tank were no more or less probable than with earlier tanks built the same way. There was no clear evidence anything was wrong with the next tank in the sequence and while foam shedding was common, the loss of large pieces was rare.

While they couldn't guarantee no such shedding during the upcoming flight, the external tank team concluded Endeavour's ET was "safe to fly with no new concerns (and no added risk)."

Despite what some viewed as a somewhat suspect "flight rationale," the FRR ended with formal clearance to launch. Endeavour's flight did not suffer any major foam damage and when when NASA managers met on Jan. 9, 2003, for Columbia's FRR, foam shedding was not on the agenda.

In that context, then, the beginning of the end came on Halloween 2002 when participants in Endeavour's FRR agreed to keep flying shuttles before gaining a thorough understanding of the bi-pod foam issue.

In "Comm Check: The Final Flight of Shuttle Columbia," co-author Mike Cabbage and I were struck by the arguments, beliefs and good intentions of smart, well-meaning engineers and managers who nonetheless missed something that seemed painfully obvious with 20-20 hindsight.

This is not meant as a criticism of the shuttle team. The system was enormously complex and distinguishing the forest from the trees was not always trivial. I certainly can't say I would have come to a different conclusion with the same information.

But to me, that FRR is where the shuttle program's fate was sealed.

"I look back on it now and say that was one of the things we really missed as an agency," we quoted then shuttle Program Manager Ron Dittemore in "Comm Check." "We had a presentation that was not thoroughly discussing the risk. And four center directors, program management, contractors and NASA -- the associate administrator for spaceflight and the associate administrator for safety for the agency -- said it was OK.

"Looking back on it, that was a critical juncture where we as an agency -- at the highest levels of our headquarters management and our program management and our contractor management and our team sitting in that room -- had a problem that was not thoroughly discussed. And we pressed forward."

The Columbia astronauts, posing for a group photo during their 16-day science mission. Back row, left to right: David Brown, pilot William McCool, Michael Anderson. Front row, left to right: Kalpana Chawla, commander Rick Husband, Laurel Clark, Israeli flier Ilan Ramon. Credit: NASA

The impact of Columbia's destruction still reverberates across the space program.

In recommendation No. 27, the Columbia Accident Investigation Board told NASA it must "conduct a vehicle recertification at the material, component, subsystem, and system levels" if the agency wanted to fly the shuttle past 2010, an undertaking that would have been enormously expensive.

Instead, in January 2004 President Bush told NASA to retire the shuttle fleet after completing the International Space Station. The idea was to free up money for new rockets and spacecraft needed to build Antarctica-style moon bases in the early 2020s.

But the Constellation moon program was never adequately funded and the Obama administration decided it was not affordable. Instead, a sharp change of course was ordered.

NASA was told to help private industry develop for-profit space taxis to ferry astronauts to and from the space station. At the same time, NASA was to continue development of the Constellation program's Orion crew capsule, focusing on a variety of deep space targets instead of bases on the moon.

NASA hopes to launch an unmanned test flight of the Orion spacecraft next year. The first commercial space taxi could blast off as early as 2015, with NASA chartered flights to and from the station starting around 2017.

But all of that depends on funding and political support in today's deficit-focused climate is uncertain at best. In the meantime, NASA is paying the Russians more than $60 million a seat to launch U.S. astronauts to the station.

It is a situation that I could never have imagined when I drove to Florida in 1981 to cover Columbia's launch on the second shuttle mission for the University of Tennessee Daily Beacon.

I went on to cover 129 of NASA's 135 shuttle missions, first with United Press International and then with CBS News. And like many who came to know the ins and outs of the space shuttle, the people who made it fly and the men and women who risked their lives to ride it, I was awed by the technical achievement it represented.

I understood there was little margin for error. I covered Challenger's final flight 27 years ago and like everyone associated with the program, I knew the shuttle was a dangerous machine to operate.

But I loved the sheer majesty of the endeavor.

I can still picture Atlantis disappearing into low clouds as it rocketed away on the 135th and final shuttle mission, feeling our building vibrate as the shock wave and a wall of sound rolled across the press site 3 miles from the pad.

I can still remember agreeing with a co-worker after Atlantis reached orbit that America needed a safer, less expensive, more up-to-date spacecraft.

And I can still remember adding, "but by God, we'll miss it when it's gone."