At 10:36 PM 2/1/03 -0500, John D. Giorgis wrote:
Space for the grieving * * * * * * * * * * At 09:00 PM 2/1/2003 -0600 Ronn! Blankenship wrote: >It would take a _lot_ of fuel to raise STS-107's orbit to the level of that >of the ISS, and probably even more to change the plane of its orbit from >39� to 51.6� inclination (not to mention any necessary rotation of the line >of nodes). IOW, if the shuttle is not originally launched into an orbit >which is meant to rendezvous with the ISS, it probably doesn't have >anywhere enough fuel on board to make such a large orbital change.What if, say, they decided that Columbia couldn't make it back to Earth, and thus they were going to make a *one-way* trip to the ISS to evacuate the shuttle? Is it likely that they would have had enough fuel for that?
Again, I doubt it, unless their mission had been planned from the first to go there and they had been launched into an orbit which would take them there. It takes a _lot_ of fuel to change the path of something moving at 5 miles per second. (F=ma, E=1/2mv^2, and all that . . . ) They would have to raise their orbit to that of the ISS, change the plane (direction) of that orbit -- the big problem -- and then insure they arrive at ISS moving only a few feet per second relative to ISS.
When people have said "_Columbia_ was too heavy to dock with the ISS", I believe that what they meant was that it doesn't carry enough fuel during liftoff to put it into an orbit with a high enough altitude and a high enough inclination to reach ISS. (I don't have the precise figures handy and for obvious reasons NASA's website is so slow that it would take me a long time to dig them out, nor is the dead tree library open at this hour of Saturday night.) A not insignificant part of its initial velocity comes from the Earth's rotation, and the larger the inclination of the desired orbit to the plane of the equator, the smaller the component of the Earth's rotational velocity in the eastward direction, so the more fuel it takes to reach a given altitude. The inclination of the orbit of the ISS is 51.6�.
Simply put: once they were in the orbit they were in, they did not have enough fuel to go to the ISS. Had there been another shuttle on the pad at KSC ready to launch, it's conceivable that they could have launched the other shuttle into an orbit which would have rendezvoused with _Columbia_, transferred the crew, and brought them home. The other shuttle would have had to reach them in time to rescue them before they ran out of consumables, of which they carry enough for a few extra days in orbit (in case of bad weather at the landing site, etc.) but not a whole lot, and I don't know of any way to resupply them except by bringing supplies on another shuttle and transferring them by hand. (The shuttle is not designed to dock with the unmanned supply rockets used to take cargo to the ISS.) Obviously, the best case scenario would be for them to discover the problem as soon as possible after they get to orbit so the astronauts stranded in orbit could do all they could to conserve consumables while the people on the ground do all they could to get a rescue mission off the ground as soon as possible. FWIW, the next scheduled mission (STS-114) was for _Atlantis_ to go to the ISS, launching no earlier than 1 March 2003. Had they known there was a problem with _Columbia_ before deorbit, I don't know how soon they could have gotten _Atlantis_ off the ground to use as a rescue craft, particularly if they could have gotten there before the crew ran out of consumables.
Not that any of that matters if they didn't know for sure that there was a problem which would make re-entry impossible . . .
--Ronn! :)
I always knew that I would see the first man on the Moon.
I never dreamed that I would see the last.
--Dr. Jerry Pournelle
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