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Columbia's Final Minutes in Detail
grub writes "This article on Newsday has an excerpt from 'Comm Check... The Final Flight of Shuttle Columbia,' by Michael Cabbage and William Harwood describing the last minutes of Columbia's final flight in detail."
While original reports used the term "plasma", there's a good explanation at space.com's Columbia FAQ that explains that the hot gas that entered the shuttle's wing was *not* "plasma", as defined by science:Not to be a science nazi, but there's an important distinction between sci-fi-sounding "plasma" and the mundane -- but still deadly -- "very hot gas".
Stressed? Me? Of course not. Stress is what a rubber band feels before it breaks, silly.
There's a memorial at Cape Canaveral with the names of ALL of the people who have died in our pursuit of outer space.
Make me a friend and I'll mod you up
Above and beyond this article, if you can get your hands on the article on the Colombia tragedy which was published in Atlantic Monthly, do it. As always for Atlantic Monthly, easily the most intelligent commentary I've seen about the event, and a couple of closing sentences that will stay with me forever.
...it's an incredible piece, and very well written. One never understands such things until it is succinctly written out, and these authors did an amazing job.
libertarianswag.com
It's murder by management if the engineers tell management "hey, this part isn't strong enough, we have to use a stronger part or some cars are going to blow up" and management says "nah, that'll cost too much, forget it". Ford Motor Company was in fact indicted for second-degree murder over the notorious exploding Pinto gas tank, after it came out that basically the above engineer-management exchange had taken place.
Similar exchanges took place before the Challenger explosion (engineers didn't want to launch until the O-ring erosion had been fixed, and management overruled them) and the Columbia crash (engineers wanted photos of the insulation damage so if necessary they could make a contingency plan, and management spiked the request). So those also fit the pattern of murder by management.
Do check out the Columbia Accident Investigation Board report at http://www.caib.us/. Or, after February 1st, go to the main NASA site and look for the links to the CAIB report.
Management and political leadership did kill.
"Beer is proof God loves us and wants us to be happy." -- B. Franklin
To be a plasma, the gas should have many free electrons (or ions) in each Debye length. There could be many more neutrals, just along for the ride, in the same space.
Most molecular gases become more or less fully ionized at around 10,000 degrees Kelvin (give or take a factor of four or so, depending on composition) since that's the temperature at which the collision energy becomes significant compared to valence electron binding energies, so most collisions can make new ions. So anything hotter than that is definitely plasma.
But even a fraction of a percent ionization is often enough to give you the nice bulk behavior of a plasma, because the ionized particles do their thing and drag along the neutral ones by collision. Depending on the density, it's probably reasonable to call the 8,000F (3800K) gases "plasma".
Parent poster is operating under a series of faulty assumptions and applying some bad reasoning.
When you've got an object traveling very vast what happens? What happens when you move your feet across the carpet? Static electricity. What is static? Electrons stripped from one object to another.
Static charge accumulates when loosely-held valance electrons transfer from less to more electonegative atoms. (Electronegativity is a measure of an atom's tendency to attract electrons.) It is analagous but not identical to dissociation, which occurs in plasma formation. Dissociation is the complete stripping of electrons from the nucleus, even the tightly-held inner shell electrons, which do not transfer when you shock someone by scuffing your feet on the rug. Dissociation, especially of diatomic gases such as O2 and N2, the major components of the atmosphere, requires immense amounts of energy. N2, for example, dissociates around 9000K (~16,000 deg F). For comparison, graphite vaporizes at about 6000K (~10,000 deg F).
Static can be a huge problem in pipes that move large amounts of non-polar fluids. Guess what most gasses in the upper atmosphere are? Non-polar fluids. So, there is your ionized high velocity, high temperature gas. Plasma.
I don't know alot about the shuttle's design, but I'd guess that if you talked with some NASA aerospace engineers they'd confirm this phenomenon. It's got to be a factor with all very fast aircraft.
Static charge is not plasma. Plasma requires complete ionization, and static doesn't even come close.
Static is not a problem insofar as flight mechanics are concerned. It may be a factor for avionics, as much as it is for any electrical system, but that is outside my area of experience.
-Carolyn
Like Daddy always said: if you can't dazzle 'em with brilliance, baffle 'em with bullshit.
1. Of the two, only Marie Curie died from causes of radiation exposure. Pierre got run over by a vehicle, but would have probably met the same fate.
2. Clarence Dally was Thomas Edison's assistance with Xrays. Here's a link.
This is not my sig.
Read the actual report of the investigating team. It's written in a very accessible style and comes to the conclusion that a rescue mission would have been possible if the problem had been discovered before reentry.
All I want is a secure system where it's easy to do anything I want. Is that too much to ask ~~ Randall Munroe
Essentially this is a myth circulated by some NASA management apologists.
...could they have hung out at the ISS and waited for NASA to send up a rescue craft?
No. Columbia was the oldest orbiter, and even though it had been refit and upgraded in many ways, it still had it's original airframe. Columbia was the heaviest of the orbiters, and unable to achieve the high orbit of the ISS. It was the only shuttle unable to make flights to the space station.
Even IF Columbia were able to achieve the altitude needed for docking, it was in an orbit that would take it nowhere near ISS. And IF it had been able to make it to ISS, Columbia did not have the docking module needed to dock to ISS. Without the docking module, the crew would need to EVA to get to ISS. Columbia did not have the spacesuits needed for this.
Columbia's ONLY option would be to wait for Atlantis, and Atlantis would have to be preped for launch in such a hurry that it's crew would be at extreme risk.
Columbia should have been retired a long time ago. We should have been using a 2nd gen shuttle by now. It may be sad to think that the shuttle fleet is to be retired with NASA's Mars goals, but in truth it was time.
I'm a big fan of the Space program, but NASA's claims that the shuttle fleet was designed to fly for 50 years should fail anybody's smell test. We don't use school buses for 50 years. Are we supposed to believe that they accounted for 50 years of metal fatigue when designing the shuttle fleet?
After Challenger NASA placed the odds for loss of a shuttle at 1 in 100. Those are risky odds. You wouldn't fly on an airplane with those odds.
The Shuttles never made the price of lauching satelites cheaper (it's primary goal) and it never made the turnaround cycle shorter than disposable launch systems.
It's time for NASA to get out of the trucking business and back to science.