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COMET LANDING -Europe set to make space history today!!
One of the biggest gambles in space history comes to a climax on Wednesday when Europe attempts to make the first-ever landing on a comet
Speeding towards the Sun at 65,000 kilometres (40,600 miles) per hour, a lab called Philae will detach from its mothership Rosetta, heading for a deep-space rendezvous laden with risk
The 100-kilogram (220-pound) probe will seek out a minuscule landing site on the treacherous surface of an object darker than coal, half a billion kilometres (300 million miles) from home
It's not going to be an easy business," was the understated prediction of Philippe Gaudon of France's National Centre for Space (CNES) as the mission prepared to enter countdown mode
The stakes facing Rosetta managers in Darmstadt, Germany are daunting as the 1.3-billion-euro ($1.61-billion) project reaches a peak.
Two decades of work have been poured into what could be a crowning moment in space exploration.
The goal: the first laboratory research into the primeval matter of the Solar System—ancient ice and dust that, some experts believe, may have helped to sow life on Earth itself.
According to this theory, comets pounded the fledgling Earth 4.6 billion years ago, providing it with complex organic carbon molecules and precious water.
Rosetta has already sent home fascinating data on the comet, but Philae will provide the first boots-on-the-ground assessment, using 10 instruments to study the comet's physical and chemical composition
Like Rosetta, it will wield a mass spectrometer, a high-tech tool to analyse a sample's chemical signature, aimed at drawing up a complete carbon inventory.
The showstopper find would be molecules known as left-handed amino acids, the European Space Agency (ESA) says.
"These are the 'bricks' with which all proteins on Earth are built," it says
View attachment 150039
Nail-biting
But getting Philae into position will be a white-knuckle ride.
After its launch in 2004, Rosetta spent 10 years zig-zagging around Earth and Mars, using the planets' gravitational pull as a slingshot to build up speed to reach its prey, Comet 67P/Churyumov-Gerasimenko
But when Rosetta finally caught up with it in August, it witnessed a sight that caused despondency back on Earth.
Far from being a simple potato shape, "67P" turned out be two gnarled lobes about four km across joined by a narrow neck.
It looked like an super-dark rubber duck, ravaged by aeons in orbit, turning slowly in space.
Its surface was a nightmare of crests and gullies, studded with hundreds of rocks as high as 50 metres (165 feet) and wicked slopes with an incline greater than 30 degrees.
This was a huge, unexpected problem, said Francis Rocard, a French astrophysicist.
"It took a billion calculations to find a decent landing site"—one offering a fair chance that Philae could survive and meet scientific goals, he said.
If final "go/no-go" assessments give the green light, Philae will separate from Rosetta about 20 kilometres (12 miles) from the comet at 0835 GMT on Wednesday.
Then it's a very gentle freefall for the next seven hours," said Sylvain Lodiot, in charge of flight operations.
After that comes the hard bit.
No one knows what a comet's surface is like.
Is it hard and crusty, like a shell? Crumbly? Slippery? Is it brittle—will it crack, causing Philae to sink into some fudgy or spongey substance below?
Seeking to cover all the possibilities, Philae's designers have equipped the lander with three outstretched legs designed to dampen the impact.
When the lab touches down, it will fire two harpoons to secure it to what—hopefully—will be a robust surface, while a thruster on top of the lander will fire to cancel out bounce. Ice screws in the lander feet will deploy for extra grip.
The chances of success? "Seventy percent," said Gaudon, admitting to days of doubt that the chances were much better than one in two.
"We need to be lucky," added Andrea Accomazzo, flight director.
And only then can Philae start its real mission of analysing the makeup of the comet.
Batteries will be enough to keep the probe going for 60 hours, but recharging from sunlight "could keep us going until March," said Rocard
Stage set for comet drama
The stage is set for the most dramatic scene yet in the epic voyage of Europe's space probe Rosetta, whose payload, Philae, will make the first landing on a comet next Wednesday:
THE SET
The historic attempt to land on a comet will take place more than 500 million kilometres (310 million miles) from Earth.
Approved in 1993, the production cost about 1.3 billion euro ($1.61 billion), involving around 200 backstage staff and 50 companies from 14 European countries and the United States.
THE CAST
ROSETTA, a three-tonne aluminium box of 2.8 x 2.1 x 2.0 metres (9.2 x 6.9 x 6.5 feet) with two 14m solar arrays.
The orbiter carries 11 instruments to map the comet's surface and analyse its atmosphere, gases in its tail, the dust it emits and its subsurface temperature, mass, density and gravity.
Rosetta got its name from the stone that led to the deciphering in the 19th century of Egyptian hieroglyphics.
PHILAE, a 100-kg (220-pound) lab named after an obelisk on the Nile whose inscriptions were a key to the Rosetta stone.
It carries 10 instruments, including X-ray detectors to scan the comet's composition, micro-cameras for panoramic shots and radiowave probes of the comet's internal structure.
Philae has a drill to take subsurface comet samples from a depth of about 20 centimetres (eight inches) for onboard chemical analysis
It will relay the results of its experiments to Rosetta, to be passed to Earth.
Its battery is charged to give it around 60 hours' operating time, but the probe could continue its work until March if the sunlight and temperature are right for its solar panels.
67P/CHURYUMOV-GERASIMENKO, a pitch-black 4-km comet named after two Ukrainian astronomers who first spotted it in 1969.
The first part of its moniker refers to the fact that it was the 67th "periodic comet" discovered—these orbit the Sun in less than 200 years.
The comet comprises two lobes joined by a narrow "neck", giving it the silhouette of a toy bath duck.
If it could be brought back to Earth, it would smell like a bad mix of rotten eggs and horse urine, among other things, tests of its escaping gases suggest.
The prime landing site, dubbed Agilkia after an island on the Nile, is on the smaller lobe roughly where the duck's forehead would be.
THE WARM-UP
Launched on March 2, 2004, Rosetta was placed in a two-and-a-half-year hibernation in June 2011 to limit power and fuel consumption on its six-billion-kilometre (3.7-billion-mile) journey.
Because there was no rocket powerful enough to place it directly into orbit, the craft was designed to be catapulted around the Solar System with gravity boosts from Mars and Earth on four flybys between 2005 and 2009.
Awoken from slumber in January this year, Rosetta arrived at the comet on August 6.
AND NOW, SHOWTIME
Once Rosetta is aligned correctly, Philae is meant to self-eject at 0835 GMT from a distance of some 20 km and unfold its three legs for what will hopefully be a gentle touchdown.
The self-adjusting landing gear is meant to ensure Philae stays upright, even if it lands on a slope. It will avoid escaping the comet's weak gravity by shooting two harpoons into its surface and using screws in its feet to secure itself to the surface.
If all goes well, signals giving confirmation of the landing will arrive on Earth at 1602 GMT
Read more at: Europe set to make space history with comet landing
@jamahir @thesolar65 @OrionHunter ..thought you might be interested...today is the D-day.
One of the biggest gambles in space history comes to a climax on Wednesday when Europe attempts to make the first-ever landing on a comet
Speeding towards the Sun at 65,000 kilometres (40,600 miles) per hour, a lab called Philae will detach from its mothership Rosetta, heading for a deep-space rendezvous laden with risk
The 100-kilogram (220-pound) probe will seek out a minuscule landing site on the treacherous surface of an object darker than coal, half a billion kilometres (300 million miles) from home
It's not going to be an easy business," was the understated prediction of Philippe Gaudon of France's National Centre for Space (CNES) as the mission prepared to enter countdown mode
The stakes facing Rosetta managers in Darmstadt, Germany are daunting as the 1.3-billion-euro ($1.61-billion) project reaches a peak.
Two decades of work have been poured into what could be a crowning moment in space exploration.
The goal: the first laboratory research into the primeval matter of the Solar System—ancient ice and dust that, some experts believe, may have helped to sow life on Earth itself.
According to this theory, comets pounded the fledgling Earth 4.6 billion years ago, providing it with complex organic carbon molecules and precious water.
Rosetta has already sent home fascinating data on the comet, but Philae will provide the first boots-on-the-ground assessment, using 10 instruments to study the comet's physical and chemical composition
Like Rosetta, it will wield a mass spectrometer, a high-tech tool to analyse a sample's chemical signature, aimed at drawing up a complete carbon inventory.
The showstopper find would be molecules known as left-handed amino acids, the European Space Agency (ESA) says.
"These are the 'bricks' with which all proteins on Earth are built," it says
View attachment 150039
Nail-biting
But getting Philae into position will be a white-knuckle ride.
After its launch in 2004, Rosetta spent 10 years zig-zagging around Earth and Mars, using the planets' gravitational pull as a slingshot to build up speed to reach its prey, Comet 67P/Churyumov-Gerasimenko
But when Rosetta finally caught up with it in August, it witnessed a sight that caused despondency back on Earth.
Far from being a simple potato shape, "67P" turned out be two gnarled lobes about four km across joined by a narrow neck.
It looked like an super-dark rubber duck, ravaged by aeons in orbit, turning slowly in space.
Its surface was a nightmare of crests and gullies, studded with hundreds of rocks as high as 50 metres (165 feet) and wicked slopes with an incline greater than 30 degrees.
This was a huge, unexpected problem, said Francis Rocard, a French astrophysicist.
"It took a billion calculations to find a decent landing site"—one offering a fair chance that Philae could survive and meet scientific goals, he said.
If final "go/no-go" assessments give the green light, Philae will separate from Rosetta about 20 kilometres (12 miles) from the comet at 0835 GMT on Wednesday.
Then it's a very gentle freefall for the next seven hours," said Sylvain Lodiot, in charge of flight operations.
After that comes the hard bit.
No one knows what a comet's surface is like.
Is it hard and crusty, like a shell? Crumbly? Slippery? Is it brittle—will it crack, causing Philae to sink into some fudgy or spongey substance below?
Seeking to cover all the possibilities, Philae's designers have equipped the lander with three outstretched legs designed to dampen the impact.
When the lab touches down, it will fire two harpoons to secure it to what—hopefully—will be a robust surface, while a thruster on top of the lander will fire to cancel out bounce. Ice screws in the lander feet will deploy for extra grip.
The chances of success? "Seventy percent," said Gaudon, admitting to days of doubt that the chances were much better than one in two.
"We need to be lucky," added Andrea Accomazzo, flight director.
And only then can Philae start its real mission of analysing the makeup of the comet.
Batteries will be enough to keep the probe going for 60 hours, but recharging from sunlight "could keep us going until March," said Rocard
Stage set for comet drama
The stage is set for the most dramatic scene yet in the epic voyage of Europe's space probe Rosetta, whose payload, Philae, will make the first landing on a comet next Wednesday:
THE SET
The historic attempt to land on a comet will take place more than 500 million kilometres (310 million miles) from Earth.
Approved in 1993, the production cost about 1.3 billion euro ($1.61 billion), involving around 200 backstage staff and 50 companies from 14 European countries and the United States.
THE CAST
ROSETTA, a three-tonne aluminium box of 2.8 x 2.1 x 2.0 metres (9.2 x 6.9 x 6.5 feet) with two 14m solar arrays.
The orbiter carries 11 instruments to map the comet's surface and analyse its atmosphere, gases in its tail, the dust it emits and its subsurface temperature, mass, density and gravity.
Rosetta got its name from the stone that led to the deciphering in the 19th century of Egyptian hieroglyphics.
PHILAE, a 100-kg (220-pound) lab named after an obelisk on the Nile whose inscriptions were a key to the Rosetta stone.
It carries 10 instruments, including X-ray detectors to scan the comet's composition, micro-cameras for panoramic shots and radiowave probes of the comet's internal structure.
Philae has a drill to take subsurface comet samples from a depth of about 20 centimetres (eight inches) for onboard chemical analysis
It will relay the results of its experiments to Rosetta, to be passed to Earth.
Its battery is charged to give it around 60 hours' operating time, but the probe could continue its work until March if the sunlight and temperature are right for its solar panels.
67P/CHURYUMOV-GERASIMENKO, a pitch-black 4-km comet named after two Ukrainian astronomers who first spotted it in 1969.
The first part of its moniker refers to the fact that it was the 67th "periodic comet" discovered—these orbit the Sun in less than 200 years.
The comet comprises two lobes joined by a narrow "neck", giving it the silhouette of a toy bath duck.
If it could be brought back to Earth, it would smell like a bad mix of rotten eggs and horse urine, among other things, tests of its escaping gases suggest.
The prime landing site, dubbed Agilkia after an island on the Nile, is on the smaller lobe roughly where the duck's forehead would be.
THE WARM-UP
Launched on March 2, 2004, Rosetta was placed in a two-and-a-half-year hibernation in June 2011 to limit power and fuel consumption on its six-billion-kilometre (3.7-billion-mile) journey.
Because there was no rocket powerful enough to place it directly into orbit, the craft was designed to be catapulted around the Solar System with gravity boosts from Mars and Earth on four flybys between 2005 and 2009.
Awoken from slumber in January this year, Rosetta arrived at the comet on August 6.
AND NOW, SHOWTIME
Once Rosetta is aligned correctly, Philae is meant to self-eject at 0835 GMT from a distance of some 20 km and unfold its three legs for what will hopefully be a gentle touchdown.
The self-adjusting landing gear is meant to ensure Philae stays upright, even if it lands on a slope. It will avoid escaping the comet's weak gravity by shooting two harpoons into its surface and using screws in its feet to secure itself to the surface.
If all goes well, signals giving confirmation of the landing will arrive on Earth at 1602 GMT
Read more at: Europe set to make space history with comet landing
@jamahir @thesolar65 @OrionHunter ..thought you might be interested...today is the D-day.
