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Columbia Coverage
ke4roh writes "Space.com offers a list of questions and answers about the events and hardware surrounding Columbia's destruction Saturday. They address suspected causes, foam, tile, and some of the alternatives had NASA known the ship would not be able to re-enter the atmosphere." viewstyle writes "PC Magazine has a pack of stuff put together on the space shuttle accident, as they recognized the fact that the space program inspired a lot of tech people in general. What's pretty cool is the section written by a guy there who worked on the computer components in the shuttle." And naturally, the idea of a space elevator is back in vogue again.
People wishing to express their sympathies can send notes to this address:
Johnson Space Center
NASA Road 1
Houston, TX, 77058
The astronauts are heroes who risk their lives to better our world. They are truly the best of the best and I think we have taken them for granted. Since Apollo, the missions they've been on haven't been attention-grabbing and shuttle launches became routine. But I think this event has awoken us to the fact that space exploration is one of the most important fields and we need to give NASA more funding. It's time to realize that space exploration is costly but to make it safe, it is even more costly. I'm also going to draft a few letters to my national representatives and let them know that NASA needs omre money. THe launch of a space shuttle is not mundane and we should still be in awe of it.
I hate liberals. If you are a liberal, do not reply.
The article on space elevators said the physics were sound, but it didn't really explain how it works. Here's the short of it:
The structure extends from earth to a point in space beyond geostationary orbit. As the earth spins, centrifugal force keeps the structure under tension to prevent it from collapsing. To place something in orbit, you just climb the structure and let go.
There's a good story about the software team at NASA here.
From the story: "Consider these stats : the last three versions of the program -- each 420,000 lines long-had just one error each. The last 11 versions of this software had a total of 17 errors."
One man's -1 Flamebait is another man's +5 Funny.
check out www.nasaproblems.com , check out his recent interview with amy goodman on 'democracy now'. he was an engineer at nasa who got ignored and reprimanded for trying to solve the problem.
"The foam is fragile enough to have been damaged once in a hailstorm, forcing a previous shuttle mission to be delayed while the insulation was repaired. Chunks have come off in flight before, too. They can be ice-coated, making them heavy projectiles. Columbia sustained damage in this way in 1992 and 1997, and foam struck a booster rocket of Atlantis in October."
RTFA
I live in the D.C. area, know many who work for NASA, and was actully at Goddard Space Flight Center in Greenbelt, MD last week doing a dog and pony show of our RMS system to their security chiefs and some of the bigwigs. I've met the people involved, higher ups and lower-downs. They dont let 7 people die to 'save face' on TV.
I don't need no instructions to know how to rock!!!!
Yes - the space shuttle was travelling fast. But the insulation fell OFF THE SHUTTLE.
s tions_answers.html#foam
Wrong:
Insulation that fell off and hit the shuttle is from the external tanks that are jetisoned after launch. Chunks fell off while shuttle was traveling at approxiamately 2x the speed of sound.
http://www.space.com/missionlaunches/columbia_que
If you know they are doomed, don't bring them back. There's a space station up there that can hold their butts until rescue arrives.
Columbia wasn't equipped to dock with the space station.
NASA believed that they had learned enough from these sensors/instruments that they were no longer needed. At some point (I'm not sure how many flights ago), NASA stopped collecting the data from them, and during Columbia's recent refit, they were removed altogether.
This was Columbia's first flight since the refit (and removal of those additional sensors), but from the briefing it seemed like even had they been aboard, they would not have been active.
Subscribers can see articles in the future? So what? Everyone gets to see them in the future.
So what the engineers will do is pull the threads. For example, it may be possible to explain all the off-scale and zero readings by assuming a particular wire bundle was cut at a certain point. This can lead them to look at the surrounding structure in more detail. They'll also look carefully at the times at which sensors went bad to determine how the structural damage evolved.
Basically the effort is to look at all possible causes of the disaster and use the telemtry to eliminate them one-by-one. Zero readings in sensors will probably be inconsistent with some possible explanations, thus eliminating them.
Read space.com. They go through all the possible rescue scenario's and conclude that it would have been impossible to save them. not enough fule to get to the ISS's high orbit, NO ONE has ever done an EVA to the underside of the shuttle (they are always in the safety of the cargo bay), no one was trained to do it, and they didn't have the equipment necessary to get to the underside of the shuttle. The only chance they would have had would be to somehow stretch out their supplies for an extra week or longer while another shuttle was rushed to the launch pad without going through the usual weeks of inspections.
In the short term, yes, a huge amount of energy, (not to mention money and materials) would have to be expended to build a space elevator. The whole point is that once it's built, moving stuff up and down requires very little energy at all. This is because energy can be generated by the lifts/shuttles/cars/climbers/whatever as they descend down the elevator, convert gravitational potential energy to, well, electricity would be probably be most useful. This energy is then used to power the lifts back up. Sure energy will be lost, but not as much as it takes to lift the entire shuttle+external tank+boosters combo up to even a low orbit.
I found this video on a Mexican news site. The story is in Spanish and mostly talks about NASA's plans for the shuttle, but the video link was new to me. It seems to show the beginning of problems with the shuttle. I haven't seen this on any US news reports or sites. Does anyone know if it's legit?
Have you seen my stapler?
Does anyone have any more details on what other parameters restrict EVAs?
The main restrictions is that you have to either be teathered or in an MMU.
They did have I think 1 suit so they could go out and fix the latches on the cargobay doors if they didn't work, but that wouldn't require leaving the cargobay.
Keep in mind, that you can't climb your way across the belly of the shuttle. There isn't anything to grab on to, and you may even do more damage than the damage you are trying to repair. That is why the tile kit (which was basically a caulking gun) was abandoned.
I do wonder whether the re-use of this tank will be seen as one of the more controversial parts of this whole operation in retrospect. There were public notices that these tanks had been retired from use, with the newer design being used in preference.
The Lightweight ETs had been used for years. The Super Lightweight ETs (which are the new tanks you are refering to) are relatively new (the first flew on STS-91). The lightweight tank (the older tank that was used on Columbia) had been used for years until STS-91. They were proven hardware. The Super Lightweight ETs were designed for ISS missions. Since Columbia wasn't going to the ISS, and NASA had 3 LWETs already built, it made sense to use one on this mission.
There are two ways for telemetry data to get from the shuttle to the ground. There are direct shuttle to Earth-based stations, but these but off as the plasma from reentry overwhelms the signal. [1]
There is a second path where data is sent from the shuttle to low orbit satellites and then onto geosynchronous satellites and back down to earth. This data was origionally automatically discarded (i.e. not passed on to mission control) as it had more than a predetermined level of static. NASA is now looking to see if any of the data that was sent is readable to see if something of those 30 cesonds can be learned. They are hoping that 50% of the data sent during that period can be read.
[1] A familiar event in Apollo splash-downs from my youth was the period that mission control lost contact with the descending command module as the plasma generated by reentry cut off radio transmissions during the actual reentry. I remember the news announcers always talking about the ablative shielding which protected the craft from the heat of reentry and that, if it ever failed, the craft would burn up as it entered the atmosphere.
I have discovered a truly marvelous sig, unfortunately the sig limit is too small to contain i
The external tank burns up when reentering the atmosphere. It is jettisoned from the orbiter just short of orbit. There is simply nothing left to recover.
- The problem with the world is that everyone is a few drinks behind. -- Humphrey Bogart
It was management that said "We have a teacher on board and a world waiting, fuck the cold weather, we have to launch now" despite a handfull of engineers saying "The o-rings could be too cold and they could crack and leak."
That's not entirely true. Sure, there was a lot of pressure, but the engineers were having a tough time convincing management that there was a problem. There had been an o-ring malfunction before (one of the two rings in a joint was burned through), but it happened in warm weather, to which NASA middle management said "see, it's not cold related," and the engineers didn't have a good response to that argument. Like it or not, you have to be able to prove your argument to win it.
There's a very good description of the problem in one of the Tufte books (a series of books on visual design and display of data, usually hawked during seminars, see http://www.edwardtufte.com). It concentrates on how not all the data was immediately available to engineers, so they made presentations (and drew conclusions) on incomplete information. Further, he argues that the data they presented was done so in a confusing, and hard to interpret, fashion. Had they had more data, they would have been able to make a much stronger case for delaying launch, but as it was, the "suits" had to go with what they knew, which was that "it seems safe enough, and nobody can convince us otherwise." (I should also mention that at least one paper takes issue with Tufte's methods and findings, but I feel that the basic truth remains -- not enough data, presented in a poor fashion, failed to convince management of the imminent risk.)
So, it wasn't so much management saying "fuck the cold," with engineers saying "they could be too cold and could leak," but instead was engineers saying "we think it could be too cold," management saying "prove it," and engineers trying to do so but not being able to present a convincing argument. Management listened, but in the end, had to go with what they knew.
FAQ Version 1.4
Link to low-bandwidth version to minimise slashdoting.
From the sci.space.shuttle FAQs
"*1* - COLUMBIA IS TOO HEAVY TO GO TO THE SPACE STATION ALPHA.
FALSE. Columbia is capable of going to the space station. However,
because Columbia's mass is greater than other orbiters, its cargo
capacity is reduced by the same amount. By using the other orbiters,
station assembly requires fewer flights since those orbiters can carry
greater mass.
During its latest heavy maintenance, Columbia's weight was greatly
reduced, but it still has a significant mass difference with the other
orbiters. Columbia was scheduled to go to the station later in 2003.
*2* - COLUMBIA CANNOT DOCK TO THE SPACE STATION ALPHA.
FALSE. During the last heavy maintenance, Columbia was modified to allow
the installation of the Orbiter Docking System (ODS). Columbia was
scheduled to go to the station later in 2003.
*3* - COLUMBIA COULD HAVE GONE TO SPACE STATION ALPHA ON STS 107 (I).
FALSE. For STS 107, Columbia did not carry the orbiter docking system. So
it could not have docked. In a bind, however, transvers via EVA (space
suits) might have been possible. The station has 2 Russian suits and 2 US
suits. Columbia has 2 US suits.
*4* - COLUMBIA COULD HAVE GONE TO SPACE STATION ALPHA ON STS 107 (II).
FALSE. Orbital mechanics and basic laws of physics make this impossible.
When a shuttle takes off, it aims in one direction and then accelerates
until it reaches its orbital speed of about 28,000km/h. This direction is
called orbital inclination.
Consider a large round frozen lake with smooth ice. You slide at 100
km/h from 12:00 to 06:00 (south) without any skates. A friend travels
from 02:00 to 08:00 (south west) at 100 km/h.
The goal is for you to shake hands with your friend while both
travelling at 100 km/h. To achieve this, you would not only have to
change your direction of travel to match that of your friend, but also do
this such that your track will match that of your friend, after which,
you can simply accelerate to catch up to him. If both are going in same
direction but 100m apart (parralel courses), you can't shake hands. Now, think
about what is required for you to change direction while sliding on ice.
Columbia launched to a 39 degree inclination. The Space station is at a
51.6 degree inclination. If you do a bit of simple algebra, changing
course 12.6 degrees while maintaining 100km/h requires about 24 km/h
acceleration or roughly one quarter of the acceleration that gave your
your 100km/h.
The shuttle accelerates from 0 to 28,000km/h during launch. Once in
orbit, the main engines are without any fuel. Only the OMS and RCS
engines are available, and their capability is roughly 1250 feet per
second, or about 1400 km/h speed change (delta v). Subtract from that the
amounts used to complete the orbit, on-orbit attitude control, as well
de-orbit burn.
If you need one quarter of the 28,000 km/h speed to change orbital
inclination, it means is 7000 km/h. So the shuttle has nowhere near what
is needed to perform a orbital plane change of 12 degrees.
Columbia was the first shuttle to fly in space. The first shuttle to fly was the Enterprise, but it was used only for drop testing and was not capable of flying under rocket power or operating in space.
Because Columbia was the first fully operational shuttle it is by far the heaviest shuttle with the lowest payload. For that reason it was not flown much after the later shuttles were built. IIRC Columbia could not reach the altitude of the space station with any useful payload.
Columbia was originally built with ejection seats on the flight deck that were later removed.
During the first few flights of the Columbia NASA was very worried about the tiles coming off. They had developed a thing a lot like a caulking gun that could be used by an astronaut to fill in the gaps left by a lost tile. But, IIRC it was never flown. So, this is a problem that NASA has considered, and one for which they already had a potential solution more than 20 years ago.
On a personal note, I can think of no better way to die than to do it while following a dream. And not just a personal dream, but a dream that benefits all of humanity. They are heros not because they died, but because they dared.
Stonewolf
They have tested an EVA helper like you describe, it is called Sprint. It flew on STS-87, ironically this was a Columbia mission and also the only other flight for Kalpana Chawla.
Remember, Amateurs built the ark. Professionals built the Titanic