Showing posts with label hanging on. Show all posts
Showing posts with label hanging on. Show all posts

Thursday, November 13, 2014

ESA Rosetta mission: Philae Lander hanging on to Comet 67/P and broadcasting

ESA Rosetta's robotic probe, Philae Lander made a historic comet landing on comet 67/P and is now said to be stable after initially failing to attach to the surface.

Pictures are coming back from the craft as scientists debate how to proceed.

The OSIRIS camera (Optical, Spectrocopic and Infrared Remote Imaging System) is vital to the mission and it would be a huge disappointment if it fails to function.

ESA Rosetta team made a statement that it is still 'not possible to analyze images from the lander, raising speculation about the state of the craft and its instruments. We are told that the radar is not working.

Has the lander landed upright after bouncing 3 times on the surface? Has it toppled in the soft surface? Has it sunk too deeply into the surface? or are the instruments simply malfunctioning?

The Rosetta team should be able to see a large part of the comet from its current location because, technically, the lander has an albedo a lot larger then the comet.

European Space Agency engineers working on the lander say it may have bounced 3 times, and lifted off hundreds of metres back up off the surface, after first touching down.

Scientists hope the probe will analyse the comet's surface to yield insights into the origins of our Solar System.

The Esa's Rosetta satellite carried Philae on a 6.4 billion-km (4bn-mile) journey to Comet 67P/Churyumov-Gerasimenko.

The robot probe, the size of a washing machine, was launched from the satellite on Wednesday and spent seven hours travelling to the comet.

News of the first landing was confirmed at about 16:05 GMT on Wednesday.

ESA Rosetta mission: Philae Lander has difficulty hanging on to comet 67/P

It was a day when science fiction became science fact. With minute-perfect accuracy, scientists landed a probe on a comet following a ten year journey through the solar system.

The European Space Agency predicted that the first signal would arrive back on Earth at 4.03pm confirming that the Philae lander had touched down after being detached from its mother ship Rosetta.

And at 4.03pm the instruments at control centre in Darmstadt, Germany, sparked into life as the probe made contact and furrowed brows were replaced with beaming smiles and tears.

“We are on the comet!” announced Dr Stephan Ulamec, Philae’s Lander Manager. “We are sitting on the surface and Philae is talking to us.”

However initial jubilation was followed by some anxiety after it emerged that the landing harpoons had not activated, meaning that the probe was simply sitting on the soft surface without being securely attached.

Just hours later Dr Ulamec was forced to admit that the scientists had lost contact with the probe and did not actually know where it was.

"It's complicated to land on a comet. It's also complicated to understand what has happened during the landing. What we know is that we touched down and we landed on the comet. We had a very clear signal and we also received data from the lander. That is the very good news

"The not so good news is that the anchoring harpoons did not fire. So the lander is not anchored to the surface. Did we just land in a soft-sand box and everything is fine? Or is there something else happening. We still do not fully understand what has happened.

"Some of the data indicated that the lander may have lifted off again. It touched down and was rebouncing. So maybe today, we didn't just land once, we landed twice."

Scientists had already spent a nerve-racking 24 hours prior to the landing trying to work out why Philae would not power up after its 10 year slumber in space.

They also quickly realised that the thruster jets, designed to help the comet stay on the surface before the landing anchors are deployed, were not working at all. Without the thrusters it was feared the probe would simply bounce off the surface and back into space.

Despite the concerns, they decided to go ahead with the detachment at 8.35am on Wednesday morning. The probe made a perfect seven hour descent onto the comet 67P/Churyumov-Gerasimenko.

But on Wednesday evening scientists were facing the agonising decision of whether to attempt to activate the anchors again and risk pushing the craft back into space, or leave the probe untethered.

“Our big concern is at the moment is whether we are standing stably. We are considering if we need to retry shooting the anchors. said a spokesman for the Philae lander in Cologne.

Yet the science community was in firm agreement that the £1.3 billion mission had been an incredible success and a huge leap forward for astrophysics.

“It is a milestone for space exploration,” said Prof Tom Marsh of the University of Warwick’s Astronomy and Astrophysics group.

“An incredibly difficult task successfully accomplished at a distance of 520 million miles. It does not get much better than this.

“To think that we have landed on an object often thought in the past to be harbingers of doom is remarkable to me. I am looking forward to what we will now learn from Philae. A truly fabulous achievement.”