Gravity (the movie, that is)

That's ONE of the reasons the movie sucked, anyway. If a missile hit a satellite and destroyed it then the pieces of debris would still have the satellite's orbital velocity plus or minus what was given to them by the explosion. Some fragments would be speeded up in the satellite's original orbit, some would be slowed down in that orbit, but most would be heading off in tangents to that orbit. Some would de-orbit and burn up in the atmosphere. All of the fragments would be potential hazards to other satellites or spacecraft but what would NOT happen is that all the fragments carried on in orbit but having all magically gained a huge amount of additional velocity in that orbit in the kind of avalanche effect dreamed of by this film's makers.

Mark you make some interesting points and I'm sorry I don't have time right now to respond to them in the depth they deserve. But I will say this: one big thing you are overlooking is that not all man-made satellites are travelling with the same orbital velocity. Many satellites are in geostationary orbits, i.e. they orbit once every 24 hours so that they are always over the same spot on the Earth's surface. Other satellites, such as the ISS, are anything but geostationary - they travel over the whole of the Earth's surface as they orbit.

Clearly then, the geostationary satellites have a very different angular velocity than the ISS. They are orbiting at different heights, naturally, so this doesn't matter. But if a geostationary satellite was destroyed and some of the debris thrown out changed altitude to the point that it was at the same altitude as the ISS< then it would already have a lot of velocity relative to the ISS. Does that make sense?

Sorry - I have to go out now.

I just watched the movie for the first time and thought it was very disapointing too.

I just watched the movie for the first time and thought it was very disapointing too.

Hi Bill, welcome to the forum. What didn't you like about the movie?