SpaceJibe

November 16, 2014

First comet drilling ever confirmed: 100% successful mission, says ESA

Filed under: Uncategorized — bferrari @ 8:24 pm

Against all odds, Philae has confirmed that the first ever drilling of a comet has happened! ESA has received telemetry data indicating that the drill worked. They also managed to send ALL data before going into sleep mode. What is Philae going to find? Perhaps the building blocks of life?

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November 12, 2014

TOUCHDOWN ! Rosetta’s Philae Probe Touches Down on a Comet !

Filed under: Comets, Gadgets, Kuiper Belt, Oort Cloud — bferrari @ 2:25 pm
Farewell Philae - narrow-angle view

Farewell Philae – narrow-angle view

ESA’s Rosetta mission has soft-landed its Philae probe on a comet, the first time in history that such an extraordinary feat has been achieved.

After a tense wait during the seven-hour descent to the surface of Comet 67P/Churyumov–Gerasimenko, the signal confirming the successful touchdown arrived on Earth at 16:03 GMT (17:03 CET).

The confirmation was relayed via the Rosetta orbiter to Earth and picked up simultaneously by ESA’s ground station in Malargüe, Argentina and NASA’s station in Madrid, Spain. The signal was immediately confirmed at ESA’s Space Operations Centre, ESOC, in Darmstadt, and DLR’s Lander Control Centre in Cologne, both in Germany.

The first data from the lander’s instruments were transmitted to the Philae Science, Operations and Navigation Centre at France’s CNES space agency in Toulouse.

“Our ambitious Rosetta mission has secured a place in the history books: not only is it the first to rendezvous with and orbit a comet, but it is now also the first to deliver a lander to a comet’s surface,” noted Jean-Jacques Dordain, ESA’s Director General.

“With Rosetta we are opening a door to the origin of planet Earth and fostering a better understanding of our future. ESA and its Rosetta mission partners have achieved something extraordinary today.”

“After more than 10 years travelling through space, we’re now making the best ever scientific analysis of one of the oldest remnants of our Solar System,” said Alvaro Giménez, ESA’s Director of Science and Robotic Exploration.

“Decades of preparation have paved the way for today’s success, ensuring that Rosetta continues to be a game-changer in cometary science and space exploration.”

“We are extremely relieved to be safely on the surface of the comet, especially given the extra challenges that we faced with the health of the lander,” said Stephan Ulamec, Philae Lander Manager at the DLR German Aerospace Center.

“In the next hours we’ll learn exactly where and how we’ve landed, and we’ll start getting as much science as we can from the surface of this fascinating world.”

Rosetta was launched on 2 March 2004 and travelled 6.4 billion kilometres through the Solar System before arriving at the comet on 6 August 2014.

Philae touchdown

Philae touchdown

“Rosetta’s journey has been a continuous operational challenge, requiring an innovative approach, precision and long experience,” said Thomas Reiter, ESA Director of Human Spaceflight and Operations.

“This success is testimony to the outstanding teamwork and the unique know how in operating spacecraft acquired at the European Space Agency over the decades.”

The landing site, named Agilkia and located on the head of the bizarre double-lobed object, was chosen just six weeks after arrival based on images and data collected at distances of 30–100 km from the comet. Those first images soon revealed the comet as a world littered with boulders, towering cliffs and daunting precipices and pits, with jets of gas and dust streaming from the surface.

Following a period spent at 10 km to allow further close-up study of the chosen landing site, Rosetta moved onto a more distant trajectory to prepare for Philae’s deployment.

Five critical go/no-go decisions were made last night and early this morning, confirming different stages of readiness ahead of separation, along with a final preseparation manoeuvre by the orbiter.

Deployment was confirmed at 09:03 GMT (10:03 CET) at a distance of 22.5km from the centre of the comet. During the seven-hour descent, which was made without propulsion or guidance, Philae took images and recorded information about the comet’s environment.

“One of the greatest uncertainties associated with the delivery of the lander was the position of Rosetta at the time of deployment, which was influenced by the activity of the comet at that specific moment, and which in turn could also have affected the lander’s descent trajectory,” said Sylvain Lodiot, ESA Rosetta Spacecraft Operations Manager.

“Furthermore, we’re performing these operations in an environment that we’ve only just started learning about, 510 million kilometres from Earth.”

Touchdown was planned to take place at a speed of around 1 m/s, with the three-legged landing gear absorbing the impact to prevent rebound, and an ice screw in each foot driving into the surface.

But during the final health checks of the lander before separation, a problem was detected with the small thruster on top that was designed to counteract the recoil of the harpoons to push the lander down onto the surface. The conditions of landing – including whether or not the thruster performed – along with the exact location of Philae on the comet are being analysed.

The first images from the surface are being downlinked to Earth and should be available within a few hours of touchdown.

Over the next 2.5 days, the lander will conduct its primary science mission, assuming that its main battery remains in good health. An extended science phase using the rechargeable secondary battery may be possible, assuming Sun illumination conditions allow and dust settling on the solar panels does not prevent it. This extended phase could last until March 2015, after which conditions inside the lander are expected to be too hot for it to continue operating.

Science highlights from the primary phase will include a full panoramic view of the landing site, including a section in 3D, high-resolution images of the surface immediately underneath the lander, on-the-spot analysis of the composition of the comet’s surface materials, and a drill that will take samples from a depth of 23 cm and feed them to an onboard laboratory for analysis.

The lander will also measure the electrical and mechanical characteristics of the surface. In addition, low-frequency radio signals will be beamed between Philae and the orbiter through the nucleus to probe the internal structure.

The detailed surface measurements that Philae makes at its landing site will complement and calibrate the extensive remote observations made by the orbiter covering the whole comet.

“Rosetta is trying to answer the very big questions about the history of our Solar System. What were the conditions like at its infancy and how did it evolve? What role did comets play in this evolution? How do comets work?” said Matt Taylor, ESA Rosetta project scientist.

“Today’s successful landing is undoubtedly the cherry on the icing of a 4 km-wide cake, but we’re also looking further ahead and onto the next stage of this ground-breaking mission, as we continue to follow the comet around the Sun for 13 months, watching as its activity changes and its surface evolves.”

While Philae begins its close-up study of the comet, Rosetta must manoeuvre from its post-separation path back into an orbit around the comet, eventually returning to a 20 km orbit on 6 December.

Next year, as the comet grows more active, Rosetta will need to step further back and fly unbound ‘orbits’, but dipping in briefly with daring flybys, some of which will bring it within just 8 km of the comet centre.

The comet will reach its closest distance to the Sun on 13 August 2015 at about 185 million km, roughly between the orbits of Earth and Mars. Rosetta will follow it throughout the remainder of 2015, as they head away from the Sun and activity begins to subside.

“It’s been an extremely long and hard journey to reach today’s once-in-a-lifetime event, but it was absolutely worthwhile. We look forward to the continued success of the great scientific endeavour that is the Rosetta mission as it promises to revolutionise our understanding of comets,” said Fred Jansen, ESA Rosetta mission manager.

November 11, 2014

Risky comet landing by European probe will be ‘7 hours of terror’

Filed under: Comets, Cool, Gadgets — bferrari @ 1:28 pm
The Rosetta mission's view of Comet 67P/Churyumov-Gerasimenko on Nov. 6, 2014. Rosetta's Philae lander will attempt to land on the comet on Nov. 12, 2014. (ESA/Rosetta/NAVCAM, CC BY-SA IGO 3.0)

The Rosetta mission’s view of Comet 67P/Churyumov-Gerasimenko on Nov. 6, 2014. Rosetta’s Philae lander will attempt to land on the comet on Nov. 12, 2014. (ESA/Rosetta/NAVCAM, CC BY-SA IGO 3.0)

Landing a probe on a comet whizzing through deep space isn’t easy, but this week, the European Space Agency (ESA) will attempt to do just that. If successful, it will be the first time a probe has landed on the surface of a comet.

The comet, which is about 2.5 miles wide, travels at speeds up to 84,000 miles per hour.

Officials working with ESA’s Rosetta mission are planning to land the robotic Philae probe on Comet 67P/Churyumov-Gerasimenko’s surface Nov. 12. You can track Philae’s historic progress in live webcasts from ESA and NASA starting Nov. 11 and throughout the day Wednesday. Officials on Earth should know if the landing went well by 11:02 a.m. EST on Nov. 12.

The landing is a risky operation.

Detailed mapping of Comet 67P/C-G only began in August, when Rosetta arrived carrying Philae. The comet’s surface is strewn with boulders and cracks, and Philae’s landing system has no way to maneuver at the last minute. [See amazing images from the Rosetta mission]

It will take about 7 hours for scientists on Earth to find out if Philae’s trip to the surface was successful. A NASA video has even dubbed that block of time “7 hours of terror,” an homage to the NASA Curiosity rover’s “7 minutes of terror” video that described the Mars rover’s landing sequence.

“This comet is very, very rough,” Andreas Accomazzo, Rosetta operations manager at the European Space Agency, said in a Google+ Hangout Friday (Nov. 7). “But this is what we have, and this is what we are trying to do. We have to be a bit lucky as well.”

First Comet Landing

If Philae’s landing is successful, it will crown Rosetta’s decade-long journey in space. The mission is doing the first orbit of a comet right now. Rosetta has already become the first spacecraft to orbit a comet, and if Philae safely touches down on Comet 67P/C-G, the lander will be the first to make a soft landing on a comet.

A comet is a tough environment. The gravity is so low that Philae will need to deploy a harpoon into the surface in order to stay put on Comet 67P/C-G. During landing, the spacecraft will face a dusty environment — not to mention, rocks on the surface. Success will also largely depend on how well the probe’s hardware and software perform during those final few hours on the way down.

Rosetta planners will spend Nov. 10 and Tuesday looking at the landing orbit and preparing the parent spacecraft to release Philae. One of the busiest times will be late Tuesday night, when controllers have only 4 hours to send commands to Philae and make sure it’s ready to go. [See more news about the Rosetta mission]

“We have 4 hours to put them together, check to verify they are consistent, uplink to the spacecraft … and double-check they are OK to the spacecraft,” Accomazzo said. “It’s a pretty dense set of activities we have to do.”

The plan then calls for Rosetta to release Philae Wednesday at 3:35 a.m. EST. (ESA officials on the ground will find out if the release was successful 28 minutes and 20 seconds later, once the signal reaches Earth.)

The spacecraft is too far away for controllers to do anything but hold their collective breath as the probe makes its descent. ESA mission controllers should acquire a signal from Philae during its descent at about 5:53 a.m. EST. Once that signal is established, Rosetta can start beaming back science information gathered by Philae on its way down to the comet’s surface.

And by about 11 a.m. EST, scientists should know if Philae reached the surface.

Rosetta will also need to make several maneuvers to stay in touch with Philae during its descent, landing and post-landing activities. ESA added that both Rosetta and Philae appear to be in good shape to date, so they are planning for the best.

Not all science would die with Philae

Even if Philae doesn’t successfully land, ESA anticipates that only 20 percent of the scientific findings expected to be gathered from the Rosetta mission would be lost. The remaining science would come from the orbital mission, which is projected to remain active until at least December 2015 — five months past Comet 67P/C-G’s closest approach to the sun.

Philae’s potential landing would make it the seventh location in which spacecraft have touched down outside Earth. The other bodies visited include Venus, the moon, Mars, Saturn’s moon Titan, and asteroids 433 Eros and Itokawa.

“It’s a very, very risky business, but it’s a business in which we have invested a lot of know-how — a lot of technical know-how, a lot of scientific know-how and a lot of cooperation,” Jocelyne Landeau-Constantin, head of European Space Operations Centre communications, said in the same webcast.

“Sometimes, we wake up and wonder if this dream is going to be true,” she added. “Sometimes, we know it can go wrong. But we are ready for every option, and are still very confident we can make it.”

Source

November 7, 2014

Scientists discover 64P comet stinks and has dunes just like Earth

Filed under: Comets, Gadgets — bferrari @ 12:41 pm

The spacecraft Rosetta keeps surprising everyone with amazing new photos taken in pursuit of comet 67P/Churyumov-Gerasimenko, taken just 7.4 kilometers from its surface. These images reveal dunes just like those you can find on Earth. Scientists have also found that it really stinks.

According to principal investigator for ROSINA, the instrument that is analyzing its composition, it really stinks:

The perfume of 67P/C-G is quite strong, with the odour of rotten eggs (hydrogen sulphide), horse stable (ammonia), and the pungent, suffocating odour of formaldehyde. This is mixed with the faint, bitter, almond-like aroma of hydrogen cyanide. Add some whiff of alcohol (methanol) to this mixture, paired with the vinegar-like aroma of sulphur dioxide and a hint of the sweet aromatic scent of carbon disulphide, and you arrive at the ‘perfume’ of our comet.

Really disgusting odor.

Sand Dunes on a Comet !

Sand Dunes on a Comet !

As for the dunes, one of the commenters at the ESA site has a good analysis:

I think I’ve decided they are deposited by the gas plumes from the surrounding cliffs firing across the already Laktritz covered floor of the “crater” Logan. Just as the mounds and dunes near cliff edges are created. No need to find a different “agent”. The gas plumes don’t have to go straight up do they.

I spotted this some time ago at the base of a cliff in the neck area. The demarcation between exposed subsurface and dust blanket, is really sharp. Now we can see why and how. The rubble strewn area to the right of image 4, the surface blanket looks like snow melting, all patchy, where thicker drifts and mounds take longer to melt. These dust mounds must be where all the dust has been “blown” and collected into quiet zones, so these little pockets take longer to be dispersed.

The chimneys I think are the “smoking guns” for the body penetrating impacts we discussed. The molten ice stuff coming out would build a wall as it immediately freezes on reaching the surface. Frozen and semi frozen ice would slowly fall back down. By the time it reaches the surface the comet has rotated so one side of the caldera has a lot more ice deposited on it. The liquid in the caldera will soon level and freeze once the gas pressure is released and the “ice lava” tube becomes blocked. This core and crater floor will have far fewer volatile ices and gases in it making it a lot less active than the surrounding surface, hence the build up of Laktritz. As the higher side of the icy crater rim takes longer to erode we are left with lots of semicircular cliffs beside flat areas.

The overturned cups are more recent eruptions where less of the crater rim has eroded. The huge flat Star Wars Landing Zone near site C. Is perched on top of huge steep cliffs, the wall of frozen ices that built up as the cryovolcano was erupting. Then we see the partially eroded rim as the cliffs round the flat area. The little cup volcanos show that an overhang actually builds up on the taller side of the rim, so this overhang eventually collapses into the crater, hence the pile of rubble only on one side of the crater. Something that is seen in nearly all the craters.

If the refrozen ices form an amorphous solid like glass, as lava does to make basalt on Earth, we get the smooth solid material full of cracks and fissures we s most commonly on the tops of the lobes. A different composition and slower flow rate would give lumpy, rubble “ice lava, (top left Image 2).. Ices with more gases in them would give a more pumice type material when it freezes, full of holes and tunnels, (Philae landing site image). A different composite of more dense volatile ices give a material like “pillow lava”, which can also be seen in image 2 as the flat topped bulges top middle.

How far this analogy can be used in actuality, I have no idea. No one else does either, since no one has seen cryovolcanism up close before, only on flyby pictures from thousands of Kilometres away. The laws of physics don’t change and the behaviour of molten fluids on freezing is a pretty well understood phenomenon. The low gravity is the big difference, though it seems to make little difference on the Moon and Mars.

Of course, that’s just speculation at this point, but it’s a fascinating idea.

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