Defunct Satellite Will Fall To Earth This Week

[cyclonic happiness]

no, it really happened! a greek playwright, Aeschylus, was killed when an eagle dropped a tortoise on his head!

Killed? surely he was just 'shell shocked'?

[frogesque]

From this point on; it's turtles all the way down!

On a brighter note (sic) it would be nice to see a really good fireball. As a (very) young lad I remember one of the Russian satelites (Sputnik 2?) streak across the northen skies of Surrey about 57 years ago

[bobbydog]

Killed? surely he was just 'shell shocked'?

oh dear....

[A.J]

Killed? surely he was just 'shell shocked'?

you should be put down for bad jokes like that!....lol

[bobbydog]

you should be put down for bad jokes like that!....lol

yes i think people should refrain from making bad jokes like that

i hope thats tortoise all a lesson...

[Jane Louise]

And there's another one lol.

As the world waits for six-ton satellite URAS to crash to Earth this week, we can reveal that a second giant piece of space junk is set for a similar fiery demise within weeks.

It wasn’t always junk. The latest doomed craft, called ROSAT, is a German space telescope that has been observing in X-ray light in an orbit 575 km above the Earth.

But atmospheric drag has already brought ROSAT – it stands for the ROentgen SATellite – to a height of less than 327 km and it has no on-board propulsion system to control its descent.

NASA experts are warning that as many as 30 fragments, weighing a total of 1.6 tons, could survive re-entry to hit the ground, including the largest chunk, the observatory’s hefty glass mirror.

It will re-enter the atmosphere at a speed of around 28,000 km per hour and disintegrate in early November. There is currently an error or plus or minus five weeks in this prediction, so the crash landing could occur in early October.

http://www.skymania.com/wp/2011/09/more-space-junk-set-to-crash-to-earth.html?utm_source=feedburner&utm_medium=feed&utm_campaign=Feed%3A+skymania%2FNZCJ+(Skymania+News+|+Space+headlines)

[A.J]

yes i think people should refrain from making bad jokes like that

i hope thats tortoise all a lesson...

...... (These 2 emoticons say it much better then words....lol)

Righty O then, NASA have come out with a little gem this stating that they've narrowed down the possible impact points with pin-point accuracy...They're 100% sure that the satellite will impact somewhere in the world between 57 degrees north and 57 degrees south....so thats 99.5% of the worlds population in the firing line currently, and they don't know what day it will happen either!.....No wonder the US government have cut their funding!....lol

[Jane Louise]

http://sites.google.com/site/uarsreentry/

[ZONE 51]

Up to 100 aircraft plummet from the skies every single week, and a causality rate of one person every one-hundred years.. continue to sleep people.

dont think theres anything to worry about then?

And there's another one lol.

http://www.skymania....Space+headlines)

so i wonder how many are on there way..might as well have an asteroid attack

Asteroids vary greatly when it comes to size. One of the smallest known asteroids, named 1991 BA, is only 20 feet in diameter. They are not visible with the naked eye. However many asteroids can be seen with binoculars or small telescopes

as i was saying, and thats a small size to be considered an asteroid as i thought they were things the size of football pitches-for example, not 20feet! .They are different from meteorites - http://library.think...8/asteroids.htm - link to the quote. Edited September 21, 2011 by ElectricSnowStorm

[bobbydog]

And there's another one lol.

As the world waits for six-ton satellite URAS to crash to Earth this week, we can reveal that a second giant piece of space junk is set for a similar fiery demise within weeks.

It wasn’t always junk. The latest doomed craft, called ROSAT, is a German space telescope that has been observing in X-ray light in an orbit 575 km above the Earth.

But atmospheric drag has already brought ROSAT – it stands for the ROentgen SATellite – to a height of less than 327 km and it has no on-board propulsion system to control its descent.

NASA experts are warning that as many as 30 fragments, weighing a total of 1.6 tons, could survive re-entry to hit the ground, including the largest chunk, the observatory’s hefty glass mirror.

It will re-enter the atmosphere at a speed of around 28,000 km per hour and disintegrate in early November. There is currently an error or plus or minus five weeks in this prediction, so the crash landing could occur in early October.

http://www.skymania....Space+headlines)

imagine being killed by a giant mirror, it would be terrible!

but upon reflection....

[Aaron]

dont think theres anything to worry about then?

Nope. Do not lose sleep over this. Remember there's 5 oceans which make up the vast majority of the earth's surface.

[Weather-history]

Anyone remember Skylab re-entry?

http://www.youtube.com/watch?v=Fy1a6JHZJq8

[Coast]

Well Runcorn may not be the only place in the spotlight. According to the Telegraph, it could land anywhere!

NASA satellite the size of bus 'could land almost anywhere'

A 20-year-old Nasa satellite the size of a bus is heading for Earth and expected to hit on Friday.

Nasa and the US Department of Defense are tracking the 35ft spacecraft, the Upper Atmosphere Research Satellite, or (UARS), as it heads towards the planet at five miles per second. Experts say there is a one-in-3,200 risk of the space junk, which weighs six tons, hitting someone. However, its speed means that there will only be a 20-minute warning before it strikes. Debris is expected to scatter across a 500-mile area, with the biggest chunk weighing 300lb, the weight of a large refrigerator.

The anticipated landing area spans cities as far north as Edinburgh and as far south as Cape Horn, on the southern coast of South America. NASA and the US Department of Defence are tracking the 35ft spacecraft, the Upper Atmosphere Research Satellite, or (UARS), as it heads towards the planet at five miles per second.

http://www.telegraph...t-anywhere.html

Handy, I need a new refrigerator.......

As of September 21, 2011, the orbit of UARS was 195 km (121 mi) by 210 km (130 mi). Re-entry is projected for 23 September 2011.Some debris may survive to reach the surface. Of the 26 pieces expected to survive reentry and strike the surface, the largest piece is expected to have a mass of 158.3 kg (349 pounds), and to reach the surface at a velocity of 44 meters/second (98 miles/hour). Smaller pieces are expected to strike the surface at up to 107 meters/second (239 miles/hour).

http://en.wikipedia....earch_Satellite

[Coast]

[Jane Louise]

The inclination of this orbit is identical to the International Space Station - any region which can have a direct fly-over of the ISS has a chance of the re-entry taking place over it.

http://sites.google.com/site/uarsreentry/

Now, how cool is that! I have seen the ISS pass over my house many times lol

[Coast]

Now, how cool is that! I have seen the ISS pass over my house many times lol

[Flash Elvis]

Not landing on me!!!

http://www.heavens-above.com/PassSummary.aspx?satid=21701&Session=kebgfdhakhelepehagdjkfin

[Coast]

Real time tracking here, but unsurprisingly the server is quite busy:

http://www.n2yo.com/

Here is another one:

http://www.infosatel...orad-21701.html

Satellite details:

http://nssdc.gsfc.nasa.gov/nmc/masterCatalog.do?sc=1991-063B

[Coast]

An amateur astronomer recorded images last week of the falling US satellite as it heads towards Earth:

Using an astrophotography camera, the French engineer was able to record the falling satellite through his 14-inch telescope as it passed 156 miles overhead.

http://legault.perso...ars_110915.html

[Coast]

What is the UARS?

The UARS is a satellite which was launched by the Discovery space shuttle in 1991 to study the ozone layer. It was decommissioned by Nasa in 2005. It is about 35ft long – the size of a bus – and weighs six tonnes.

Why it is coming to Earth?

After being decommissioned it was inevitable that the satellite would drop out of orbit at some point. On Sept 7 Nasa announced that it would fall to Earth in weeks.

Where will it hit?

Nasa's guess is as good as yours. It could come down anywhere between 57 degrees north and 57 degrees south of the equator, which leaves out the poles but covers most of the populated world. The space agency's latest estimate is that it will arrive on Earth on Friday evening, and they have reassured US citizens us that "the satellite will not be passing over North America during that time period." It could still land almsot anywhere in Europe, Africa and Asia. This map gives a good sense of the likely impact zone.

Much of the satellite will burn up in the atmosphere, but experts estimate that 26 pieces – the largest weighing 300lb, the same as a large refrigerator – will be scattered over an area of up to 500 miles.

Are humans at risk?

Technically, yes. Probably, no. The odds of anyone at all being hit by the debris are about one in 3,200. Multiply this figure by the world's population and that means the chance of you being hit is roughly one in 20 trillion. Given that most of the Earth's surface is covered by water, it is most likely that the satellite will land with a splash rather than a crash.

Has this happened before?

It has indeed. The last satellite to crash down to Earth was the Skylab in 1979, which was 15 times heavier than the UARS. It landed in Western Australia but the US kindly footed the clean-up bill.

No one has ever been hurt by space junk falling to Earth, but it is worth keeping an eye out if only for the potential for a spectacular light show. Sputnik's return to Earth in 1958 was a fantastic affair, leaving a trail of bright sparks as it raced from New York to the Amazon in ten minutes.

Why there is so much uncertainty?

The satellite's unorthodox shape means it is tumbling to Earth in an unpredictable spiral rather than plunging down like an arrow. Factors like the warmth of the air and the amount of drag make it impossible to tell exactly how it will come down. Also, space debris can bounce – meaning that when it hits our atmosphere it could skim across it like a stone on a lake before re-entering.

If it lands in my garden, can I keep a bit?

Afraid not. Even if it's completely useless, it is still the property of the US government.

http://www.telegraph...ill-it-hit.html

[weatherobsuk]

Its also important to remember that IF the satellite comes down Europe-side, there'll be little to no '20 minute prior' warning other than relying on observers from shipping or flights Eastern Atlantic side. I also wonder going from that notice wether any NOTAMs will be issued tomorrow because of this, 6 tonnes of component parts raining out the sky isn't going to be aircraft friendly, especially its effectively carpet bombing a wide area than coming down as a singular unit.

[Coast]

Its also important to remember that IF the satellite comes down Europe-side, there'll be little to no '20 minute prior' warning other than relying on observers from shipping or flights Eastern Atlantic side. I also wonder going from that notice wether any NOTAMs will be issued tomorrow because of this, 6 tonnes of component parts raining out the sky isn't going to be aircraft friendly, especially its effectively carpet bombing a wide area than coming down as a singular unit.

I also wonder what you could do about it if they gave a 20 minute warning? Would you stay put or drive several miles away? Either way, you are unlikely to avoid a fast moving, wide spread mass of space debris breaking up on re-entry if it is coming right for you - the thing being, no one knows exactly where it is going to fall! You might as well stay put and not worry about it. Lets hope it gives us a light show at worst

[weatherobsuk]

Good point, my best bet if you was downwind of the 20min prior warning, would be to face somewhere sheltered facing East. The satellite debris will be coming Westwards and i'd imagine still carrying the same lateral trajectory as it's coming into the lower regions of the atmosphere (give or take friction), but it at least raises the odds of missing of if behind a Eastern facing slope, cliff, or wall. Of course we'll probobally never get a warning at all, or in the very least it'll just end up plopping into the ocean never to be seen again.

[Snowangel-MK]

I also wonder what you could do about it if they gave a 20 minute warning?

Not much you could do about it by then....apart from putting the 20 minutes to good use

[Coast]

The US space agency (Nasa) says that its out-of-control climate satellite is expected to crash to Earth sometime on Friday evening (GMT).

There is still much uncertainty over when and where the satellite will re-enter the atmosphere. Experts say they will get a more precise idea in the last 12 hours before the satellite is due to return. The US space agency says the risk to life from the Upper Atmosphere Research Satellite (UARS) is 1 in 3,200. Satellite and space expert Dr Stuart Eves stressed the large uncertainties involved in tracking the "decay" of satellite orbits (their slow fall back into the Earth's atmosphere).

Using the most recent determination of UARS' orbit - taken in the early hours of this morning - Dr Eves and a colleague have come up with their own projections of the satellite's final descent. But he explained that a spacecraft's orbit lifetime could only be estimated to about 10% accuracy. This translates to a six-hour window either side of the expected decay which, based on a range of probabilities, would see the spacecraft splash down in the Southern Ocean. But given the 10% accuracy figure, and the fact that UARS takes about one-and-a-half hours to complete an orbit of Earth, the satellite could come down during one of four possible orbits of Earth on Friday evening/Saturday morning.

And a number of different estimates could be produced depending what software is used to model the satellite's decay, Dr Eves explained. Satellite decays can be affected by a number of different factors, such as the shape of the satellite and its unpredictable tumbling, as well as heating of the Earth's atmopshere by ultraviolet radiation from the Sun. This can make the atmosphere expand, causing UARS to fall to Earth faster than expected. But other conditions could see the satellite stay in space for longer than anticipated.

Nasa says that debris could fall across an area 400-500km (250-310 miles) long. In its latest update, the space agency said only that the spacecraft would "not be passing over North America" when it is expected to be pulled through the atmosphere to Earth. The spacecraft could pass over Britain during its final passes over the planet. Given that some 70% of the Earth's surface is covered by water, a splash-down for the debris seems most likely. But there remains a real possibility that some debris could fall on land. UARS could land anywhere between 57 degrees north and 57 degrees south of the equator - most of the populated world.

The 1 in 3,200 risk to public safety is higher than the 1 in 10,000 limit that Nasa aims for. But agency officials stress that nobody has ever been hurt by objects re-entering from space. And Dr Eves points out that meteorites were falling to Earth all the time. The US satellite was deployed in 1991 from the space shuttle Discovery on a mission to study the make-up of Earth's atmosphere, particularly its protective ozone layer. Nasa has warned members of the public not to touch any pieces of the spacecraft which may survive the re-entry, urging them to contact local law enforcement authorities.

http://www.bbc.co.uk...onment-15021323