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Subscribe to RSSAerospace engineers from Analytical Graphics Inc. used the company's analysis and visualization software to create this video, showing the UARS satellite in its current orbit, its potential debris area, and models for its burn-up and breakup. More info: http://blogs.agi.com
Update for 4:30 p.m. ET Sept. 23: NASA revised its forecast since this report was first posted to note that the Upper Atmospheric Research Satellite was not sinking as quickly as expected, and that there was a "low probability" that debris from the re-entry could fall on North America. The revised forecast said the satellite could come down late Friday or early Saturday, Eastern Daylight Time.
Earlier report from Wednesday: NASA says its derelict Upper Atmosphere Research Satellite is expected to make its final fiery plunge sometime on Friday afternoon ET and notes that "the satellite will not be passing over North America during that time period."
This afternoon's update suggests that Americans are not at any risk for injuries or property damage due to satellite debris. It also means they'll miss out on the fireworks.
For two weeks, experts on orbital debris have been telling people that the 20-year-old, bus-sized spacecraft would soon fall through the atmosphere and drop about two dozen pieces of debris on Earth — but until today, there was too much uncertainty to say exactly which day that would happen. In the morning update, NASA narrowed the time frame down to Friday. The forecast was refined further at 6:35 p.m. ET. But NASA said it couldn't yet be any more precise than to say it'll be Friday afternoon, Eastern Daylight Time.
"It is still too early to predict the time and location of re-entry with any more certainty, but predictions will become more refined in the next 24 to 48 hours," NASA said.
The six-ton satellite's orbit is limited to between 57 degrees north latitude and 57 degrees south, spanning the width of the world between northern Canada and the tip of South America. In the past, Nicholas Johnson, the head of NASA's Orbital Debris Program Office, has estimated that the chances that any of the UARS debris would hit anybody were 1 in 3,200 — which translates into a 1-in-20 trillion risk for any particular person.
NASA's Johnson told me today that he won't be recalculating the odds as the prediction becomes more precise. "At that point, we don't compute odds," he said.
NASA and its partners at the U.S. Strategic Command will be issuing updates on the timing at 24 hours before the expected fall, then at T-minus-12 hours, T-minus-6 hours and T-minus-2 hours — and we'll be passing those predictions along. But even two hours before re-entry, experts won't be able to project exactly where the debris will end up.
When UARS' predicament first came to light a couple of weeks ago, Johnson said the margin of error for the 500-mile (800-kilometer) fall zone would be somewhere around 6,000 miles, or a quarter of the way around the planet. The uncertainty arises because of a couple of factors: Solar outbursts, like the ones we've been getting over the past few weeks, lead to a faster decay of orbits for low-flying spacecraft. Also, the satellite is tumbling, which leads to unpredictable atmospheric-drag effects. Because there's no fuel left for orbital maneuvering, no one has any control over UARS' orbital course.
Most of the satellite will burn up in the atmosphere, but NASA estimates that about a half-ton's worth of fragments will survive re-entry and fall to Earth. The computer models suggest that the biggest chunk would weigh about 300 pounds (150 kilograms), or as much as a refrigerator. Anyone who happened to be in the vicinity of the debris fall would see bright streaks in the sky, much like the fireworks seen when pieces of Russia's Mir space station fell to Earth in 2001.
The most likely outcome is that the remnants of the UARS satellite would fall into a desolate patch of ocean or an uninhabited stretch of land, far away from any witnesses or potential victims. "Throughout the entire 54 years of the Space Age, there has been no confirmed report of anybody in the world being injured or severely impacted by any re-entering debris," Johnson noted two weeks ago.
A dead satellite the size of a school bus is getting lower and lower and will crash into Earth, NASA said. The best guess is that it falls on Friday. NBC's Brian Williams reports.
UARS was deployed from the shuttle Discovery in 1991, beginning a $750 million mission to study the upper atmosphere and its interaction with the solar wind. In 2005, it was shut down and placed into a disposal orbit, and its altitude has been slowly decaying ever since. Now the descent is picking up speed: NASA said its altitude at 1:30 p.m. ET today ranged from roughly 120 to 130 miles (190 to 205 kilometers).
Nowadays, satellite operators lay out a well-defined procedure for the safe disposal of Earth-orbiting satellites at the end of their lifetimes. In fact, NASA and its international partners are already devoting attention to what needs to be done when it comes time to get rid of the International Space Station, sometime after 2020. But back in the 1990s, when the UARS mission was launched, such issues were "really not given a lot of thought," Johnson said.
Update for 9 p.m. ET: If North America is out of the picture, what about the rest of the world? Take a look at the graphic on this webpage from The Aerospace Corp. to see why NASA has ruled out North America based on its time estimate.
The circled icon on the map indicates the position of the UARS satellite at 4 p.m. ET Friday. The blue curves show its orbital track before 4 p.m., and the yellow curves show the track after 4. If UARS re-enters the atmosphere before 4, the potential fall zones include the Atlantic, Africa, Middle East, north Asia and the Pacific. If it happens after 4, South and Central America, south Asia and Australia come into the mix. But it'd be well into Friday evening by the time the orbital track goes over the U.S. and Canadian East Coast.
More about the satellite saga:
- Watch the doomed satellite tumble in space
- FEMA ready if plunging satellite hits U.S.
- Who'll get hit by a falling satellite?
- Real-time UARS tracking from N2YO.com
Check NASA's UARS status page for updated information about the satellite's whereabouts, all the way to the end.
Connect with the Cosmic Log community by "liking" the log's Facebook page, following @b0yle on Twitter or adding me to your Google+ circle. You can also check out "The Case for Pluto," my book about the controversial dwarf planet and the search for other worlds.
Leave a Comment:
Why don't they just blow it up like the chinese, and directly after, the americans did a while back? Why not just blow it up again?
Watch it fall on poor people in the 3rd world as if they don't have enough misery.
Yeah it's on its way to Mexico. But that's good karma though because they fuked up our country (U.S) as well.
This really shouldnt be a week long article...how cares anymore?
Of course it's going to miss the U.S. It's going to where all of the other trash is dumped...MEXICO! :D (Compliments of NASA)
The Corporate world would have products to sell the person's family that the debris hits such as funerals, coffins, monuments, plots, and the like.
Big of the Corporations and Unions to have this stuff available to sell.
Perhaps the union officials and corporate officers could all be in one place on Friday, is it? Include the music and entertainment businesses for sure. Members of the media. Keep 'em tightly arranged.
I don't find thisone bit funny. Correct me if I'm wrong but Americans put this thing up there, right? Then America has the nerve to say 'Whew-this thing isn't going to hit us when it lands...it will probably hit some poor suckers in another country'!
Do you all have any idea how bad that sounds? Do you even care about anyone besides your own citizens?
Typical American arrogance. Disgusting.
Do you always judge a nation by the comments of the ignorant few? First consider that this is the Newsvine, and it hardly represents the sane, rational citizens of our country. No, this is for the ones who like to spread hate, call others with different beliefs names, and in general amuse themselves by posting garbage for the rest of the bottom feeders to feast on.
In all fairness to the responsible posters, not everyone here is uncaring, rude, and hateful. I see many people with good minds who stick to fact, and attempt to have intelligent discourse on these forums. So please take that into consideration before you judge all of us.
all we have to do is "pray" that no one will be hurt.
So it isn't coming down anywhere near the Fox News Channel headquarters?
That 1 in 3200 is the odds that it will hit even one person, anywhere. If that 1 in 3200 chance does happen, and it hits someone--then divide that by the 7 billion or so people now living to get the odds that it will hit YOU. Very small odds.
wouldn't you think by now, that to save money, more bang for the buck, to send it on a deep space journey mapping the galaxy, sending signals and pictures from another solar system, noooooo, we got to play hit the humans for 10 points with a satelite, come on guys, recycle, reuse, new purpose, i think we got satelites going out of solar system or gone already, where are their signals? what is beyond the unknown? you know what i think, they are scare to do it, cause an alien might find it, come to earth and have MChuman burgers and fries. i would have put a couple of rockets on it and send it to alpha centurie, our neighbor, if we are lucky, they might try send a massage back to us. recycle, reuse, or is going green is just a joke.
All we have to do is "pray" that no one gets hurt.
I have dibs on it landing mostly in the ocean.... (:
Well it's current velocity is 16,812 mph and it's altitude varies little at 130 miles. I thought these things fall when they go below 17,000 mph. It's rate of decay is real small.
I have an idea, ya man, let's send up a cool shuttle, you know, the one we kept around for an emergency, just in case we needed one, like in this instance, you know like that ray smith dude suggested just a few weeks ago, it could drop a tether on it and yank it up to higher orbit then open the cargo bay doors and then pull it inside with that really cool robotic arm built in canada....oh wait....nevermind....
we'll see where it lands when it lands, till then there are still plenty of variables, I remember just a couple of years ago they were scratching their heads over why a sat prematurely deorbited...later they found out the atmosphere shrank, then they scratched their heads over why that happened....honestly it's all physics, but any physicist will tell you this or that should happen, but you can't collect the data till AFTER the event.
Mexico?...I hope not, besides I miss all those cheap tomatoes and fruits and vegtables, it is not like droves of unemployed americans rushed out to take those jobs as the migrants vacated the us, naw, most of those I know draw some type of assistance check, I note the ones that wanted free big computer monitors from me grab it at the first chance, march on out to thier car whilst I watch, mumble it's ok under their breath as I tell them to wait so I can at least help them with the trunk lid, then, the part I love, when I ask them how that bad back that got them that assistance check is now that they toted that 80lb monitor is doing?..oh, ow, ow, ow...normal response, I try to think of something clever to mumble like tu penga or what not....naw, if your gonna drop a bus on mexico, at least make it bus full of counterconception stuff....bu@!$%#es...
well! hope no one gets hurt. just "pray"
We get it Vivien, you don't have to keep posting the same thing over and over.
It's lowest altitude is 118 miles so it has to cut that in half before it starts burning up
you would think that with the economy in the shape it's in. that a satelite which cost billion of dollaers to produce and to launch into orbit that somthing could have been done to salvage the satelite and reuse it's parts to build a new one. i guess our goverment just can't resites wasteing our taxpayor dollars why not reminde them of how they let billion of dollars burned up in reentry give them that billion dollars .
had to get the flame proof suit on with the wimp helmut (one never knows where those weakly interacting particles are...)
so heres the answer: within about 300 years, wantonly dropping stuff from orbit is gonna be a big no, no, replete with big fines from the world court, I note that ocean farming is likely to ramp up, population density will continue to increase and, somehow, (fuzzy on this one), common sense will prevail. It will dawn on those people that 1) REAL SPACESHIPS DO NOT BOUNCE and 2) something like a reusable shuttle with cargo bay doors and a robotic arm would be a nice thing to have, particularly in gathering up debris, thus, the space shuttle will be resurrected...it will be a dc-10 of leo and mid space commericial space activities, surely re-engineered, and perhaps take off like a real space ship should (without all the thunderous smoke and noise). It will surely take focus, something lacking today. A sense of true economic accounting, again something lost today (16 bucks for a muffin?..sure, five bucks for a coffe, why not?). A realization of the need, (if this thing were to hit a favorite celebrity, boy you'd here it then!). And a group of leaders that lead effectively, no parenthesis necessary.
I know there are people out there that do not want to here that. Too bad.
Looks like it is wrapped in gold, with gold close to $2000 an ounce was hoping it would come dwn near me.
That gold will be long scattered in little pieces before it hits any ground. Now any surviving internal electronics is another matter.
Gold would be nice but as Mike pointed out it will be long gone. I'd be looking for the titanium pieces that are leftover, just don't sell them on e-bay cause the govt. will come and take them away from you.
They have said that FEMA was ready if it does hit the US. Since when has FEMA ever been ready for anything?