1. There are several scenes which depict space debris reaching the astronauts’ location, with catastrophic results. While the impact of these collisions are probably realistic, it’s highly improbable that this debris would be visible (you can spot many objects approaching, missing or hitting Sandra and George’s location) mainly because of their ultra high speed relative to the astronauts’ area. Remember, we are talking about orbits with speeds in the order of several 10k’s of km/h.
2. When the Chinese space station is de-orbiting, and the atmosphere is stripping parts off the outside, Dr Ryan Stone is inside with objects floating about her. In reality, there would be a small deceleration caused by the atmospheric drag that would pull all objects to the front of the craft.
3. The shuttles original mission was to service Hubble, yet when the shuttle is wrecked, Kowalsky moves with Stone to the ISS, which just happens to be “a short hike away.” In reality, Hubble orbits at an altitude of 595km (the topmost service roof of the Space Shuttles), while the ISS does so at an altitude of 340km. Furthermore, even if they had been able to see the ISS from Hubble’s orbit, they would have only seen it speed ahead, as their orbital velocities are different: 7.66km/s for the ISS and 7.58km/s for Hubble, a difference of 75m/s / 270km/h / 167.78mph.
4. When Stone makes it to the Chinese station, it is experiencing reentry. This is nothing but a drama-making mistake, as the station would have needed to have been actively boosted down/slowed down for it to have been a deliberate deorbit, or have had its navigation completely neglected for months or years for its orbit to decay to that point. In either of these two cases, it could not have been orbiting at a fixed position with the otherwise-stable ISS.
5. During the first few minutes, before all the comsats get taken out by the debris storm, conversation between Houston and the Space Shuttle include Quindar tones. Quindar tones are the sharp beeps attending each voice transmission. These tones are obsolete and haven’t been used for many years.
6. Outside on her spacewalk Bullock has a watch over her suit. Inside after she removes the spacesuit, she is watchless while moving through the 1st “ship” she entered (wearing the T-shirt and shorts) then suddenly it appears on her wrist again.
7. In several scenes, Sandra Bullock used radio equipment in efforts to call for assistance. There is a sound made by vintage, mechanically tuned radios called “heterodyning” that results in a squealing, variable frequency sound in the speaker. While heterodyning added a degree of drama to the scenes in “Gravity”, contemporary digital radios operate on a different, highly stable technique for tuning, and do not produce heterodyne sounds.
If you want to watch the trailer for Gravity, you can below