(meteorobs) UARS Satellite expected to reenter atmosphere in 3-5 days

[Skywayinc at aol.com]

Set my alarm and got up early this morning to view a  predicted 
near-overhead pass of the UARS satellite over my home in 
Putnam Valley, NY.  
 
The NW to SE pass came pretty much on schedule  between
5:47 and 5:50 a.m. (according to Heavens-Above).   As expected,
movement was quite rapid . . . it streaked across the  sky much
quicker than the ISS or the Space Shuttle.
 
During the three or so minutes I had it in view, the  satellite slowly
rose in brightness from about magnitude 3 to 0, then  suddenly 
flared/flashed in brightness to about -2 or -3, then  quickly dropped
off to near-invisibility.  Then the whole sequence  began anew.  It
did this a total of three times before it vanished  behind the treetops
in my southeast.  The thing must be  tumbling.
 
There is another high pass scheduled for tomorrow  morning . . . 
UARS will emerge from the Earth's shadow near its  highest point
in the sky of nearly 80-degrees at around 5:30 a.m.,  then a 
relatively low evening pass is set for Saturday at  around 7:40 p.m.
(if it's still in orbit).  
 
Unfortunately, a protracted spell of cloudy  weather is expected 
to settle in tonight and last much of this week, so  perhaps this 
morning was my last view. of UARS.

-- joe rao 

 
 
In a message dated 9/19/2011 6:53:09 A.M. Eastern Daylight Time,  
meteoreye at comcast.net writes:
 
Prepare for UFO and fireball reports!
 
This will be an uncontrolled reentry, so could occur anywhere from 57  
degrees N to 57 degrees South latitude.
 
Latest estimate is Sept 23 +/- 1 day
 
The risk assessment is interesting reading:
 
_http://www.nasa.gov/pdf/585584main_UARS_Status.pdf_ 
(http://www.nasa.gov/pdf/585584main_UARS_Status.pdf) 
 
Total dry mass at start 5668 kg
 
– Number of potentially hazardous objects expected to survive: 26 
– Total mass of objects expected to survive: 532 kg
– Estimated human casualty risk (updated to 2011): ~ 1 in  3200 
 
• No NASA or USG human casualty reentry risk limits  existed when UARS
was designed, built, and launched.
 
• NASA, the USG, and some foreign space agencies now seek to limit  human
casualty risks from reentering space objects to less than 1 in  10,000.
 
• UARS is a moderate-sized space object. Uncontrolled reentries of  objects
more massive than UARS are not frequent, but neither are they  unusual.
 
– Combined Dragon mockup and Falcon 9 second stage reentry in June  2010 
was more
massive.
 
• Since the beginning of the space age, there has been no confirmed  report 
of an injury resulting from reentering space objects.
 
• NASA, DoD, and the IADC will be monitoring the decay and reentry of  UARS
carefully.


-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://lists.meteorobs.org/pipermail/meteorobs/attachments/20110919/59a2a607/attachment.html