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Failed Phobos-Grunt (Mars Mission) To Crash Into Earth

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A Russian spacecraft launched this week destined for Mars has yet to leave Earth orbit – and looks increasingly likely to tumble back to Earth with its full tanks of dangerous toxic fuel.

Russia’s space agency has all but given up hope of saving the 100million pounds spacecraft that was bound for Mars but conked out shortly after launch, the Daily Mail reported.

The spacecraft weighs 14.6 tons, and most of that weight (about 12 tons) is a highly toxic mix of nitrogen teroxide and hydrazine fuel.

Engineers had three days to fix a problem that caused the Phobos-Grunt probe to shut down before batteries aboard the craft died for good.

The engines that were supposed to propel it on its way to the red planet failed to ignite, but any attempts to correct the failure seemed doomed as scientists admitted that they couldn’t even establish communications with the craft.

Now that the deadline has come and gone, Phobos-Grunt will run out of battery life and begin a decaying orbit around the Earth until it - and the 12 tons of dangerous fuel it is carrying - makes an unwelcome and uncontrolled return to the surface.

Roscosmos spokesman Alexei Kuznetsov said efforts to communicate with the unmanned Phobos-Grunt hadn’t brought any results.

He said controllers were still working to fix the probe but there was little likelihood they would be successful.

The Russians are hoping the fuel will stay liquid when the probe comes down, harmlessly exploding about 50 miles above ground.

But experts like James Oberg, a NASA veteran who now works as a space consultant, think the fuel could freeze, surviving the fiery re-entry and causing an environmental disaster on impact.

He said the probe would become ‘the most toxic falling satellite ever’ and added “What was billed as the heaviest interplanetary probe ever may become one of the heaviest space derelicts to ever fall back to Earth out of control, an unenviable record.”

An interesting one to watch.

History of program: link

Keep up to date on gooble news : link

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Update: link

The Russian space agency has conceded there is now little chance of reviving its Mars mission, Phobos-Grunt.

The probe has been stuck circling the Earth since its launch on 9 November, unable to fire the engine that would take it on to the Red Planet.

Engineers have tried in vain to contact the spacecraft, and Roscosmos deputy head Vitaliy Davydov said the situation now looked very grim.

"One should be a realist," he was quoted as saying by RIA Novosti.

"If we've been unable to establish communication with [Phobos-Grunt] for such a long time, there are few chances that we shall fulfil the expedition now," were his comments reported by the Russian news agency at a press conference in mission control centre at Korolev on the outskirts of Moscow.

"If we establish contact [with the probe] and begin to understand what's wrong with it, then we shall be able to draw some conclusions," Davydov said.

Later, another Russian news agency, Interfax, quoted Davydov as saying that Phobos-Grunt might fall from orbit anytime between late December 2011 and February 2012.

"It is an interesting question how [the probe] will behave. There is fuel on board. If there is an explosion, it is one thing, but if it simply starts falling apart with no explosion, then it is another thing," Interfax reported the deputy head as saying.

The spacecraft weighed some 13 tonnes at launch - double the mass of Nasa's recently re-entered UARS satellite.

What is more, most of the 13 tonnes is made up by the propellants unsymmetrical dimethylhydrazine (UDMH) and dinitrogen tetroxide (DTO), both of which are toxic.

If the Phobos-Grunt mission is truly lost, then professional and amateur groups will be modelling its orbit in an attempt to determine precisely where and when it might come down.

As with UARS, much of the spacecraft will burn up in the atmosphere; but any parts made of high-temperature metals, such as titanium or stainless steel, stand a chance of making it all the way to the surface.

Indeed, it is the fuel tanks that often survive the fall because their spherical shapes enable them to spin up and dissipate heat more easily.

However, the probability is that any debris would hit the ocean, given that more than 70% of the Earth's surface is covered by water. This was the case with UARS and the German Rosat X-Ray telescope that returned to Earth last month.

To date, Phobos-Grunt has been maintaining its orbit, but trackers will be monitoring the spacecraft closely to catch any change in its behaviour.

The probe was built to land on the Martian moon Phobos and scoop up rock for return to Earth. Such a venture would yield fascinating new insights into the origin of the 27km-wide moon and the planet it circles.

The mission was also notable because China's first Mars satellite, Yinghuo-1, was launched piggy-back on the main Russian spacecraft.

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http://www.zdnet.co.uk/news/emerging-tech/2011/11/24/stricken-space-probe-phobos-grunt-sends-more-data-40094504/

The first successful attempt to contact the probe was made on Tuesday night and, on Wednesday night, further telemetric data was received. This data should tell Russian mission controllers about the health of Phobos-Grunt's systems, and perhaps reveal why it is in an unplanned orbit around Earth, rather than travelling to the Martian moon Phobos as intended.

"The spacecraft's radio downlink was commanded to switch on and telemetry was received," European Space Agency (ESA) service manager for Phobos-Grunt, Wolfgang Hell, said in a statement. "The signals received from Phobos-Grunt were much stronger than those initially received on 22 November, in part due to having better knowledge of the spacecraft's orbital position."

http://www.bbc.co.uk/news/science-environment-15841896

Later, another Russian news agency, Interfax, quoted Davydov as saying that Phobos-Grunt might fall from orbit anytime between late December 2011 and February 2012.

..

What is more, most of the 13 tonnes is made up by the propellants unsymmetrical dimethylhydrazine (UDMH) and dinitrogen tetroxide (DTO), both of which are toxic.

If the Phobos-Grunt mission is truly lost, then professional and amateur groups will be modelling its orbit in an attempt to determine precisely where and when it might come down.

As with UARS, much of the spacecraft will burn up in the atmosphere; but any parts made of high-temperature metals, such as titanium or stainless steel, stand a chance of making it all the way to the surface.

Indeed, it is the fuel tanks that often survive the fall because their spherical shapes enable them to spin up and dissipate heat more easily.

Sounds like they haven't made up their minds yet.

Perhaps they should redesign the fuel tanks so that this doesn't happen? Or are they spherical for other reasons needed in space flight?

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Perhaps they should redesign the fuel tanks so that this doesn't happen? Or are they spherical for other reasons needed in space flight?

Possibly more stable (less roll) if it's liquid.

Saw a documentary about a gas carrier tanker with spherical tanks and better sea-worthiness.

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Possibly more stable (less roll) if it's liquid.

Saw a documentary about a gas carrier tanker with spherical tanks and better sea-worthiness.

Also the lightest shape for a tank for a given amount of fuel (maximum volume for a given amount of metal). Weight saving is probably an important consideration.

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Or are they spherical for other reasons needed in space flight?

Spherical tanks distribute the pressure of gas/liquid in the tanks more evenly so there is less risk of a leak or explosion - this is especailly true of high pressure liquids/gases used in space flight.

This is not the sole reason but mainly the shape of a tank for a given liquid/gas is determined by the liquid/gas that will be contained in it - high pressure, low pressure, etc - and how explosive the liquid/gas itself it.

Spheherical tanks cost a lot more to manufacture as the process of bending metals can lead to microscopic fractures which weaken the tanks. If you see a sphereical tank it is undoubtedly containing a high pressure liquid/gas.

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Either way, there's about a 75% chance of it landing in the sea, and perhaps a 1% chance of landing in an inhabited area if it doesn't. While a few tons of hydrazine crashing down in your back yard would be a really bad day, it shouldn't have much effect beyond the impact zone and its surroundings.

It's probably worth noting that one of the Apollo crews accidentally fed this stuff into their capsule when they screwed up the landing checklist, and they survived. It's toxic, but not 'get a single drop on your skin and die' toxic.

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Update: Re-entry Jan 6-9th

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Russia's space agency (Roscosmos) says its unsuccessful Mars probe will fall back to Earth next month.

The unmanned Phobos-Grunt spacecraft became stranded in orbit in November.

The agency says it expects the toxic fuel on board to burn up on re-entry, but 20-30 fragments of the spacecraft will survive to the surface.

Current Roscosmos estimates for the timing of the fall are between 6 and 19 January, but this window will be narrowed nearer the event.

Professional and amateur groups around the world will also be modelling the decay in the orbit in an attempt to determine precisely where and when Phobos-Grunt might come down.

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So the same scientists that predict the toxic fuel will burn up in the atmosphere are also the ones who expected this spacecraft to be a success?

God help us.

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So the same scientists that predict the toxic fuel will burn up in the atmosphere are also the ones who expected this spacecraft to be a success?

From what I've read, the only people who expected it to be a success would appear to be the managers who pushed them to launch on time regardless of whether it was ready.

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So the same scientists that predict the toxic fuel will burn up in the atmosphere are also the ones who expected this spacecraft to be a success?

God help us.

To be honest the fuel is probably the least of your worries.

The flaming chunks of metal would probably pose a more immediate threat.

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Update:Aussies on alert for deadly alien encounter as Russian Mars probe hurtles toward Earth

Aussies on alert for deadly alien encounter as Russian Mars probe hurtles toward Earth

A failed Russian Mars probe laden with toxic fuel may soon crash land in Australia.

According to a report on News.com.au on Tuesday, a failed Russian Mars probe laden with toxic fuel may soon crash land in Australia.

A scientist quoted by the site calls the Phobos-Grunt — an 8.5 tonne spacecraft fueled by a "poisonous propellant consisting of unsymmetrical dimethylhydrazine and dinitrogen tetroxide" — the most toxic falling satellite. Ever.

Phobos-Grunt was supposed to land on the larger of Mars' two moons, Phobos, and gather rock samples to study back on Earth.

However, after suffering "total battery failure" in November, it's wound up hurtling toward Earth at 18,640 miles per hour instead.

And while Russia's space agency (Roscosmos) has already said the toxic fuel on board will likely burn up on re-entry, 20-30 fragments of the spacecraft — around 440 pounds worth — are expected to survive to the surface, the BBC reported earlier this month.

Optimistically, the beeb wrote that:

With more than 70 percent of the Earth's surface covered by water, the chances are that any fragments that do survive the fiery re-entry will end up in the ocean.

However, News.com.au rains on that parade, reporting that:

Phobos-Grunt is moving around Earth at an altitude between 201km and 275km, meaning it will fall anywhere between latitude 51 degrees north and latitude 51 degrees south, which encompasses all of Australia.

Reentry is reportedly expected between Jan. 6 and 9

If a piece of space junk is going to land anywhere and miss major population centers, it may as well be Australia: according to research by migration consultants ASA, 97 percent of land Down Under remains uninhabited — or virtually so — mainly due to it being uninhabitable (ie. desert).

To put it another way, about 90 percent of the population lives in about 3 per cent of the land area, and that's mainly around the coast.

Besides which, Australia's Spaceinfo.com.au editor Jonathan Nally reportedly says the toxic stuff should burn up as the probe fell through Earth's atmosphere.

"These chemicals are just lethal, very nasty, but we should be safe from them because of the incredible heat of re-entry," he reportedly said. "After all, this stuff is meant to burn and this probe doesn't have heat shields."

Then there's this reassuring thought from Nally:

"It's orbiting at 30,000 kilometers [18,640 miles] per hour, that's traveling 10,000 kilometers [6,214 miles] every 20 minutes, so if someone's calculations are out by just 20 minutes that means where they predict the probe will fall could be [6,214 miles] out."

Who knows — Los Angeles is around 11,000 miles from Sydney, so if calculations are 40 minutes out... You do the math.

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Phobos-Grunt is moving around Earth at an altitude between 201km and 275km, meaning it will fall anywhere between latitude 51 degrees north and latitude 51 degrees south, which encompasses all of Australia.

That's London and South. This could prop up safe Northern house prices.

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