NASA: Satellite Debris Probably Hit Pacific, But Room For Doubt 65
An earlier report that debris from the recently deorbited UARS satellite had landed in Canada may have been premature. Apparently, the picture of when (and therefore where) the satellite deorbited is back to being clear as mud. Most likely, says NASA, the debris will never be found, but is thought to have landed in the Pacific Ocean. If you're an optimist interested in finding your very own piece of space debris, though, you might be interested in this map based on various re-entry scenarios (hat tip to Robert Woodcock); in the U.S., the Northwest is your best bet.
Re:A little confused... (Score:5, Informative)
Re:A little confused... (Score:5, Informative)
From what I understand, UARS was intentionally decommissioned and was instructed to perform a burn to (eventually) bring it down.
Yes. When it was decommissioned several years ago, it used its last bit of fuel to bring it to a lower orbit so that it would come sooner.
Don't we have more deliberate and controlled ways to de-orbit satellites?
Yes. Nowadays, that is part of the mission planning for satellites. (Well, at least for NASA satellites...)
Or is it just too complicated and expensive to add that kind of functionality considering the extreme odds of actually hitting anything valuable?
That was the thinking in days when UARS was launched.
Nowadays, even that tiny risk is considered important enough to justify controlled de-orbiting. Mainly for PR reasons, I think.
In addition, we now realize that leaving dead satellites hanging around in a low orbit for a few years runs the additional risk of it colliding with something and causing an explosion of space junk.
Re:A little confused... (Score:5, Informative)
It takes a LOT of fuel to break orbit. To little and it will come back eventually. Why waste a buttload of fuel to lift all that extra fuel into orbit just so the satellite has enough fuel left so it can break orbit. It's much easier and cheaper to deorbit by bringing it down and letting gravity do the work.
Re:A little confused... (Score:5, Informative)
Gravity at ISS: 9.1 m/s^2
Satellites are still very much inside Earth's gravity well. They are not floating in space, they are constantly falling but their tangential velocity ensures they miss hitting the Earth.