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Unmanned Spaceflight.com _ Earth Observations _ Rest In Peace Uars

Posted by: BPCooper Dec 14 2005, 11:51 PM

The Upper Atmospheric Research Satellite, deployed Sept. 12 1991 from the Space Shuttle Discovery, was decomissioned today. It's last good battery shorted out in August and planning to end the mission went as planned and concluded today with the shutting down of the satellite. Last week, a several-minute burn lowered the orbit of the satellite.

It is expected to make an uncontrolled reentry in 2008 or 2009. UARS opened a wealth of understanding on the upper and lower atmospheric layers including monitoring the ozone layer.

Posted by: djellison Dec 14 2005, 11:58 PM



Always sad to see a great spacecraft come to the end of it's life, but it's an opportunity to reflect on all that it has taught us.

Doug

Posted by: BruceMoomaw Dec 15 2005, 03:17 AM

The Earth Radiation Budget Satellite -- launched by Shuttle in 1984 -- is also finally about to be turned off. It's a measure of how difficult it is to study global warming without satellites that, until ERBS, we were in the dark about even such a fundamental question as whether Earth's current cloud cover is warming or cooling the planet! (The answer, provided by a few years of ERBS observations, is that it is significantly cooling us.)

Posted by: djellison Dec 15 2005, 08:44 AM

At least the GERB instrument on the first MSG ( made right here in Leicester ) can take up from ERB.

Is the sort of data that UARS was taking being filled in for by the A-Train?

Doug

Posted by: BruceMoomaw Dec 15 2005, 11:13 AM

I believe so (although I'd have to review my documents on the A-Train). Certainly the "Aura" satellite is supposed to make improved versions of most of UARS' observations, and I believe all of them.

Posted by: RNeuhaus Dec 15 2005, 02:00 PM

QUOTE (djellison @ Dec 14 2005, 06:58 PM)
Always sad to see a great spacecraft come to the end of it's life, but it's an opportunity to reflect on all that it has taught us.

What a nice is that virtual UARS.

Rodolfo

Posted by: happypete Jan 27 2006, 09:10 PM

QUOTE (BPCooper @ Dec 14 2005, 07:51 PM)
It's last good battery shorted out in August


Actually, according to the final weekly report, both remaining "good" batteries were performing acceptably up to the end. One must presume that the passivation of the system was driven by the gradual decline in available power and other failures, and the availability of science data from instruments on other birds.

Posted by: Spin0 Sep 12 2011, 06:43 PM

UARS re-entry is expected during the last week of September 2011.

NASA and U.S. Strategic Command will give updates here: http://www.nasa.gov/mission_pages/uars/index.html

Posted by: happypete Sep 14 2011, 01:41 PM

QUOTE (Spin0 @ Sep 12 2011, 01:43 PM) *
UARS re-entry is expected during the last week of September 2011.


Thanks for the update. It looks like UARS stayed aloft a lot longer than originally predicted after they passivated it in 2005. Typical behavior, though, for a satellite that stretched its "eighteen month" minimum design life into 14 years of valuable reporting on our planet's upper atmosphere.

smile.gif

Posted by: SolarSystemRubble Sep 19 2011, 11:25 AM

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

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.

Posted by: Spin0 Sep 20 2011, 09:47 PM

Thierry Legault shot a video of the tumbling UARS: http://legault.perso.sfr.fr/uars_110915.html

Re-entry still expected by Sept. 23 +- a day.

As of Sept. 20, 2011, the orbit of UARS was 127 mi by 140 mi (205 km by 225 km). Re-entry is expected Sept. 23, plus or minus a day. It is still too early to predict the time and location of re-entry. Predictions will become more refined over the next two days.
http://www.nasa.gov/mission_pages/uars/index.html

Posted by: SolarSystemRubble Sep 21 2011, 02:10 PM

As of 1000 UTC today, the orbit is down to 195 x 209 km (121 x 130 mi) falling at a rate of 8 (perigee) and 11 (apogee) nper day.

This has not yet been incorporated into the reentry time forecast, that's still based on yesterday's orbit update, which predicted Sept 23 20:36 UTC +/- 20 hours:

http://reentrynews.aero.org/1991063b.html

When it get down to about 120 km, the atmosphere grabs it, and it falls during that orbit.

MW/SSR

Posted by: Holder of the Two Leashes Sep 22 2011, 06:19 PM

North America has just been ruled out of the strike zone.

Dang, and I was planning a walk in O'Brien park.

Posted by: SolarSystemRubble Sep 22 2011, 06:44 PM

By who? The latest map has a stripe across north americas two orbits after the center time of the reentry window, as well as the following 2.

Orbit is now 184 x 195 km, deccreasing at 9 and 13 km per day. The end is near

Map:

http://reentrynews.aero.org/1991063b.html

Posted by: PDP8E Sep 22 2011, 08:18 PM

...from the site cited in the last post:

Reentry Prediction:
Predicted Reentry Time: 23 SEP 2011 @ 22:07 UTC ± 9 hours

± 9 hours means 6 orbits
where are the perigee points? They are the most likely places where UARS starts to sink into the atmosphere

( that may be why (maybe) North America has been ruled out? (by whom?) )

Personal Plea: Please make these interminable clouds go away!

Posted by: SolarSystemRubble Sep 22 2011, 08:45 PM

QUOTE (PDP8E @ Sep 22 2011, 03:18 PM) *
...from the site cited in the last post:

Reentry Prediction:
Predicted Reentry Time: 23 SEP 2011 @ 22:07 UTC ± 9 hours

± 9 hours means 6 orbits
where are the perigee points? They are the most likely places where UARS starts to sink into the atmosphere


I would assume (and it's just an assumption) that it's at the the point of most likely reentry as shown on the map.

Posted by: Holder of the Two Leashes Sep 22 2011, 09:25 PM

Here is one source ...

http://www.space.com/13050-falling-nasa-satellite-north-america-safe.html

Best to only read the story and ignore the comments.

Posted by: SolarSystemRubble Sep 22 2011, 09:56 PM

QUOTE (Holder of the Two Leashes @ Sep 22 2011, 04:25 PM) *
Here is one source ...

http://www.space.com/13050-falling-nasa-satellite-north-america-safe.html

Best to only read the story and ignore the comments.



Well that's certainly far different than the map that I posted... We shall see.

Posted by: SolarSystemRubble Sep 22 2011, 10:00 PM

BTW, the map has been updated with the latest orbital elements. It is now sept 24, on an orbit that crosses the US 20 minutes later.

Sept 24 0058 UTC +/- 7 hours (5 orbits). That's about 9PM EDT

http://reentrynews.aero.org/1991063b.html

Posted by: Floyd Sep 22 2011, 10:47 PM

That is 9pm EDT on the 23rd (in US and Pacific target) 1 am 24th in UK. Time zones rolleyes.gif

Posted by: SolarSystemRubble Sep 22 2011, 11:42 PM

QUOTE (Floyd @ Sep 22 2011, 05:47 PM) *
That is 9pm EDT on the 23rd (in US and Pacific target) 1 am 24th in UK. Time zones rolleyes.gif


Yeah thanx, I should have mentioned it's the 23rd evening in the US.

Posted by: MahFL Sep 23 2011, 03:38 AM

Last info I read said it would NOT be over the USA......

Posted by: Explorer1 Sep 23 2011, 04:11 AM

South Pacific now:
http://reentrynews.aero.org/1991063b.html

(not too far from Mir back in 2001)

Posted by: SolarSystemRubble Sep 23 2011, 07:22 AM

That's the same map I posted 6 hours earlier, it hasn't ben updated since. Besides the time is +/- 7 hours, so I wouldn't focus of any particular orbit yet.

BTW, I see a NOTAM has been issued...

Posted by: Explorer1 Sep 23 2011, 04:54 PM

Over the Sahara now. Still mostly empty areas.

Posted by: PDP8E Sep 23 2011, 08:45 PM

http://reentrynews.aero.org/1991063b.html

the reentry point is now in Africa

it like 3 Card Monty !

Posted by: Floyd Sep 23 2011, 08:53 PM

I don't know if aero.org does any independent analysis or just works off of http://www.nasa.gov/mission_pages/uars/index.html. Unfortunately they have not updated from report #10 at 10:45 am EDT this morning. Maybe they are waiting until one orbit left to post...

Posted by: Silmfeanor Sep 24 2011, 01:10 AM

First post ! biggrin.gif

The latest info -
145 x 150 km, 56.9° (Epoch Sep 23)
Reentry expected in the next 2-4 hours!

Posted by: SolarSystemRubble Sep 24 2011, 02:43 AM

Just some more details...

Latest update as of 2215 UTC, demise is ~ 7 hours away (3 hours now), and the US is finally off the table.

Orbit at that time (about 4 hours ago) was 145 x 150 km (90 x 93 mi). Down 17 and 20 km in the preceeding 12 hours.

Estimated crash time is 0510 UTC Sept 24 +/- 2 hours, over the very south Pacific west of Australia, although the earlier and later orbits include Canada, Africa and Australia of the landmasses.

MW

Posted by: ElkGroveDan Sep 24 2011, 04:45 AM

It should be down by now, or very soon.

QUOTE
UARS Updates

Update #12
Fri, 23 Sep 2011 07:50:07 PM PDT

As of 10:30 p.m. EDT on Sept. 23, 2011, the orbit of UARS was 85 miles by 90 miles (135 km by 140 km). Re-entry is expected between 11:45 p.m. Friday, Sept. 23, and 12:45 a.m., Sept. 24, Eastern Daylight Time (3:45 a.m. to 4:45 a.m. GMT). During that time period, the satellite will be passing over Canada and Africa, as well as vast areas of the Pacific, Atlantic and Indian oceans. The risk to public safety is very remote.


Posted by: Holder of the Two Leashes Sep 24 2011, 04:59 AM

UNCONFIRMED reports (from twitter) that it may have come down over Quebec 40 minutes ago.

Posted by: ElkGroveDan Sep 24 2011, 05:10 AM

Also, earlier lights reported over Edmonton would make sense as the first pieces started to come off. Pretty certain this is accurate.

Posted by: Explorer1 Sep 24 2011, 05:23 AM

Northern Quebec's pretty empty (but not so empty that pieces can't be recovered). Can't wait till morning!

Posted by: brellis Sep 24 2011, 05:41 AM

Hope no one wakes up with a headache or a new skylight!

Posted by: Holder of the Two Leashes Sep 24 2011, 06:29 AM

Several independent reports coming in from southern Alberta about a debris trail in the sky moving rapidly.

Posted by: Sunspot Sep 24 2011, 08:37 AM

now saying the pacific

Posted by: SolarSystemRubble Sep 24 2011, 10:25 AM

NASA Statement:

Update #15
‎Today, ‎September ‎24, ‎2011, ‏‎3 hours ago
NASA’s decommissioned Upper Atmosphere Research Satellite fell back to Earth between 11:23 p.m. EDT Friday, Sept. 23 and 1:09 a.m. EDT Sept. 24. The Joint Space Operations Center at Vandenberg Air Force Base in California said the satellite penetrated the atmosphere over the Pacific Ocean. The precise re-entry time and location are not yet known with certainty

Posted by: Floyd Sep 24 2011, 11:45 AM

That is a rather long window for splashing in the Pacific. I was up in the night so followed the activities on Twitter. IamUARS was great fun. Really expected more from NASA; NASA_Watch; and other sites, but alas little real information has yet been released.

Posted by: SolarSystemRubble Sep 24 2011, 12:10 PM

If it did indeed come down over the Pacific, there aren't a lot of eyes out there...of any kind.

Of course the breathless reports are coming in all over from what were probably common meteors. Due to the media storm, people who have never looked at the sky before were peering upward, and for last night, everything wasn't a UFO, it was a UARS smile.gif

Posted by: djellison Sep 24 2011, 01:33 PM

QUOTE (Floyd @ Sep 24 2011, 03:45 AM) *
Really expected more from NASA; NASA_Watch; and other sites, but alas little real information has yet been released.


That's because little information exists. What do you want NASA to do - make stuff up?

They reported all the info they had as quickly as can be expected.

Posted by: Paolo Sep 24 2011, 02:01 PM

QUOTE (SolarSystemRubble @ Sep 24 2011, 02:10 PM) *
over the Pacific, there aren't a lot of eyes out there...of any kind.


millions of fishes and other creatures disagree... smile.gif

Posted by: SolarSystemRubble Sep 24 2011, 02:26 PM

QUOTE (Paolo @ Sep 24 2011, 09:01 AM) *
millions of fishes and other creatures disagree... smile.gif


True, but most don't communicate with Space Command or NASA smile.gif

Posted by: Floyd Sep 24 2011, 04:12 PM

QUOTE (djellison @ Sep 24 2011, 09:33 AM) *
That's because little information exists. What do you want NASA to do - make stuff up?
They reported all the info they had as quickly as can be expected.


I wasn't trying to give NASA a hard time, just thought other US agencies who track space objects and threats would have passed NASA some information. We have spy satellites that would have picke up the IR signal of reentry etc. It will probably just take a while for this information to get declassified and released.

Posted by: SolarSystemRubble Sep 24 2011, 04:16 PM

Update #16
‎Today, ‎September ‎24, ‎2011, ‏‎37 minutes ago
NASA’s decommissioned Upper Atmosphere Research Satellite fell back to Earth between 11:23 p.m. EDT Friday, Sept. 23 and 1:09 a.m. EDT Sept. 24. The Joint Space Operations Center at Vandenberg Air Force Base in California said the satellite entered the atmosphere over the North Pacific Ocean, off the west coast of the United States. The precise re-entry time and location of any debris impacts are still being determined. NASA is not aware of any reports of injury or property damage.

This is your source for official information on the re-entry of UARS. All information posted here has been verified with a government agency or law enforcement.

NASA will conduct a media telecon at 2 p.m. ET to discuss the re-entry. The telecon will be streamed live at www.nasa.gov/newsaudio.

Posted by: SolarSystemRubble Sep 24 2011, 06:36 PM

Map of Final orbit with most likely point where center of debris track would be at 10 km height.

http://www.nasa.gov/pdf/591662main_UARS%20Map.pdf

Posted by: MahFL Sep 26 2011, 01:18 PM

Also at the peak of the re-entry time, the tracking website was overloaded...as always happens during "events".
Also I cannot believe the US DOD don't know EXACTLY where the debris splashed/impacted.....


ph34r.gif ph34r.gif ph34r.gif ph34r.gif


Posted by: stevesliva Sep 26 2011, 08:17 PM

QUOTE (MahFL @ Sep 26 2011, 09:18 AM) *
Also I cannot believe the US DOD don't know EXACTLY where the debris splashed/impacted.....


It's conceivable. You'd have to conclude they know where Mars 96 is, too. That's tinfoil hat territory.

Posted by: gwiz Sep 27 2011, 10:57 AM

USSTRATCOM is now quoting decay time as 0400 GMT plus or minus one minute.

Posted by: SolarSystemRubble Sep 27 2011, 07:21 PM

QUOTE (gwiz @ Sep 27 2011, 05:57 AM) *
USSTRATCOM is now quoting decay time as 0400 GMT plus or minus one minute.


That's even further out in the Pacific then...

Posted by: nprev Sep 29 2011, 04:33 AM

Apparently a very good outcome: remote area of S. Pacific:

http://news.yahoo.com/nasa-satellite-fell-south-pacific-not-canada-201709293.html

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