Earlier this week, NASA announced that one of its satellites, the Upper Atmosphere Research Satellite
(UARS), will come tumbling out of the sky sometime later this month or in early October. Most of the spacecraft--the size of a schoolbus (5.7 metric tons)--will burn up in the atmosphere, although 26 pieces are expected to survive reentry.
But don't worry, the sky's not falling. According to NASA, space debris falls out of the sky all the time; none of the 26 pieces contain toxic material; and in the 54-year history of the space age, no one has been injured by falling space junk.
Yet there are some concerns: "This is the largest NASA satellite to come back in quite some time," says Nick Johnson, chief scientist, NASA’s Orbital Debris Program. "An object the size of UARS typically reenters once a year." And, since the satellite is basically inert and not maneuverable, NASA won't know when or where it will fall, except that it could be anywhere from 57 degrees north latitude to 57 degrees south latitude. That could be anywhere from northern Canada to southern South America.
Using AGI's analysis and visualization software, we created the video below showing UARS in its Sept. 9, 2011 orbit. The inset shows its ground track--where it is over Earth on each orbit. In upcoming weeks, we will follow NASA's informational posts and update our video to show what's going on up there. So, check back occasionally to see what's new.
And those of you who have downloaded our Satellite AR app for Android can look for the satellite as it goes overhead. All you have to do is key "UARS" into the search box, tap the search results, hold up the camera, and see if it's overhead.
UARS image on front page: Courtesy NASA