NASA satellite in fiery plunge this week
FROM TODAY'S PRINT EDITIONS:
NASA’s defunct UARS satellite is expected to re-enter the Earth’s atmosphere in a fiery, uncontrolled plunge sometime in the next few days.
UARS was launched in 1991 from the shuttle Discovery. Designed to study the upper atmosphere for three years, the bus-sized spacecraft was finally decommissioned in 2005.
It orbits between 57 degrees north and south latitudes, and will fall somewhere within that range. The pass nearest to Baltimore was over N.J., at 5:29 a.m. today.
(NASA PHOTO)
Posted by Frank Roylance at 12:09 AM | Permalink
| Comments (3)
Categories: From the Sun's print edition, Sky Notes
Categories: From the Sun's print edition, Sky Notes
Comments
Was there any info on why it is falling now after 20 years, and how they know it will be in the next few days?
FR REPLIES: After the satellite was decommissioned in 2005, engineers moved it into a lower orbit that would bring it down sooner, rather than 20 years later. That's why it's in the news now. Every satellite, spent booster and hunk of space junk that's big enough to detect is being tracked by the U.S. Strategic Command, along with its rate of descent. (For a sense of how vast the list is, check out the "Satellite Database" on Google Earth.) That's allowed UARS to be followed, and estimates to be made of when it will come down. Even so, even within a few hours of its fall, there's still enough uncertainty that its impact "oval" is thousands of miles long. The good news is that two-thirds of the Earth is water, and most of the land is lightly inhabited. Space junk falls every day, most of it burns up, and no one (so far) has ever been injured. This happens to be an especially big one, with components that will survive the fall. International agreements for some years have required the owners of spacecraft to build in mechanisms to enable controlled re-entries, or to move expired satellites into safe "graveyard" orbits at the end of their useful lives. Even so, some still fail and their owners lose control.
Posted by: Susan | September 20, 2011 11:06 AM
Frank: Just an FYI that those agreements weren't in place back when this was designed/launched/decommissioned.
FR REPLIES: Guess I didn't make that clear. Thanks.
Posted by: Mike Singer | September 20, 2011 4:13 PM
Is there any guess to when it will fall. I'm sure there are lots of people who would like to see the fire works.
FR REPLIES: Best guess is sometime, somewhere, Friday. Unfortunately, there are no passes in that time period that would make the fall visible from Maryland.
Posted by: Headshots Los Angeles | September 21, 2011 1:33 PM