Corrected entry: To increase the chance of success, there's a backup for everything: we have 2 crews, with 2 shuttles, 2 armadillos etc. However, when we get the crisis where the government wants to blow up the nuke before the hole is finished, there is only one bomb. Isn't there a second nuclear bomb in the shuttle that crashed?
Correction: When the shuttle is careening out of control, a bunch of equipment is flying out of it. It's possible the nuclear bomb was sucked out as well.
Corrected entry: A few things about splitting the asteroid always annoyed me. They couldn't possibly calculate that drilling a certain depth would "split" the asteroid rather then blowing it to smaller but still deadly bits. Even if they did calculate right they did this on stable rotation. But as they stated the asteroid started rotating unpredictably after passing the moon so it could have turned towards earth causing one piece to hit as they calculated and the other to hit just a bit later. And last even if all 2 previous scenarios go just right (as in the movie) we saw that the asteroid was covered with huge high and sharp "mountains" which would most likely break of in the explosion and rain down on earth. So either way earth would be doomed.
Correction: In regards to the moon, the asteroid started to rotate after passing the moon, not change its trajectory. Thus the two pieces (if sucessfully split) would most likely miss earth. Furthermore, in a weightless environment, the two pieces would be pushed apart by the explosion with the same amount of force. Thus the trajactory of both pieces would be the same (but in opposite directions) from the moment it exploded. In regards to the sharp mountains, they aren't big enough to "doom" the earth and would mostly burn up upon entering the earth's atmosphere.
Correction: With regard to the assumption that the asteroid would split in half, there are a few mentions of a fault line on the asteroid, so it seems like NASA has scanned the asteroid enough to determine that placing the nuke at a certain depth will indeed split it along that fault line. As to the rotation issue, the graphic that shows the rotation indicates it is not spinning end over end but around its central front-to-back axis, so NASA calculates that the nuke splitting the rock in half would still work.
Corrected entry: Considering their space suits are made to measure, where did the Russian get his special anti-zero gravity suit from?
Correction: The suits they use on the asteroid could be universal as we can see two unused suits in the scene when Harry and AJ takes the elevator down for the last time.
Correction: I assume NASA had them carry extra spacesuits just in case.
Corrected entry: One of the things the creators of the movie did not think out is the issue of the asteroid's gravity. There are several problems with that. It is stated that the asteroid is the size of Texas. Even if we assumed it to have had 1000 miles of diameter (a really huge asteroid) and the same density as Earth it would have gravity of about 12% of Earth's gravity. In the movie it can be seen (even though stated otherwise) that the teams operate under earth-like gravity - tools, piping elements, debris all fall down with quite an acceleration. Also the astronauts move about very conveniently - much more easily than would for example on the Moon. On the other hand if we assumed that the asteroid had much higher density, which allowed it to had significant gravity, a near passing (a couple of hundred kilometers) of such a massive body alone would probably wipe out humanity just as efficiently as a direct hit. Even if we assumed that the asteroid's diameter was only 500 miles and its density was about the density of the Moon, the near passing of its two halves would wreak havoc on Earth as the influence of their gravity on, for example, ocean tides, would be up to 20 times bigger than Moon's.
Correction: Gravitational forces don't have to be equally distributed throughout an astronomical body. They have what are called mass concentrations, or mascons, which are clusters of material beneath the surface of higher density than the rest of the object, while the body as a whole has a lower average gravity (mascons in the Moon had to be accounted for in adjusting Apollo mission lunar orbits). So the Roughnecks could just be working on a higher density area.
Correction: They lost communications with that ship and (presumably) everything on it. That's why they say nothing about detonating the second bomb.
Timothy Conard