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Margaritabrief extract from ESA Rosetta blog:HIGHLIGHTS – MEDIA BRIEFING 10 NOVEMBER
...The first science sequence lasts about 2.5 days (depending on battery life). If solar power recharges the batteries, we go into long-term surface science.
In summary, everything is in great shape and we are counting down to an exciting and crucial delivery day
University of Leicester planetary scientist explains the significance of the European Space Agency's historic Rosetta satellite mission
MargaritaNature: Landing on a comet: A guide to Rosetta’s perilous mission
A graphical guide identifies the dangers ahead for the Philae probe.
Elizabeth Gibney
10 November 2014
A PDF download is available from Nature. Click here
Never before has a space mission put a lander on a comet. But the European Space Agency (ESA) plans to change that. Its Rosetta craft has been orbiting comet 67P/Churyumov–Gerasimenko since August and is set to release the washing-machine-sized lander, Philae, on 12 November. This would set in motion a nail-biting seven-hour fall designed to deliver Philae to a landing site called Agilkia on the comet’s surface. Philae is programmed to beam data and images back to Earth to help scientists to understand comets, including whether these conglomerations of ice, rock and dust supplied our planet with water and other building blocks of life when they smashed into it billions of years ago. Our step-by-step guide identifies the biggest obstacles to a successful landing — although even if the landing fails, it will go down as one of the most ambitious feats attempted in space.
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European Space Agency http://new.livestream.com/ESA/cometlanding
about 6 hours ago ·87,094 Views
Hear our comet sing
Rosetta’s Plasma Consortium (RPC) has uncovered a mysterious ‘song’ that Comet 67P/Churyumov-Gerasimenko is singing into space. The comet seems to be emitting a ‘song’ in the form of oscillations in the magnetic field in the comet’s environment. It is being sung at 40-50 millihertz, far below human hearing. To make the music audible to the human ear, the frequencies have been increased in this recording:
A singing comet
The Excerpts from the Guardian live coverage of Philae landing
11:10 GMT
Signal acquired from Rosetta
After a tense few minutes longer than expected, the signal has been re-aquired from Rosetta. It is relaying telemetry from the lander. So, now we can follow Philae all the way to the surface of the comet. Data and images will begin downlinking now. Touchdown in about five hours from now.
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12:18 GMT
Below is the first of a trio of music videos released today by Esa to celebrate the first ever attempted soft landing on a comet. Vangelis composed the piece specifically to mark the Rosetta mission.
He is best known for his Academy Award–winning score for the film Chariots of Fire, and the score for Blade Runner. His music was used in Carl Sagan’s epic documentary series Cosmos.
The composer says:
Mythology, science and space exploration are subjects that have fascinated me since my early childhood. And they were always connected somehow with the music I write.
Click to play embedded YouTube video.
MThink geezer with a PhD: the tattooed Londoner on inspiring ‘ancient comet ninjas’ at the European Space Agency
When researchers ask children to draw a scientist they usually receive vaguely Einstein-looking figures, people in lab coats or men with facial hair. From now on, they could start seeing extensive tattoos on those characters as well.
Inspiring this new look is Dr Matt Taylor, the man in charge of the science being done by the European Space Agency’s Rosetta mission to land on a comet for the first time and hopefully reveal secrets about how life began on Earth.
Much of Taylor’s body is covered in tattoos. Worried about image, the space agency asked him to cover his arms at a large media event this year. Now, the tattoos have become a talking point. He even has one dedicated to the comet mission on his right thigh. He’s from Manor Park, north-east London. His father, a bricklayer, was convinced his son could do better and impressed upon him that physics would be a good subject because it was “the science of everything”.
Edit to put in this link with detailed explanation of the landing procedure: https://www.mps.mpg.de/3086295/Philae-BlogFrom the Guardian live Coverage
12 November 2014 17:03 GMT
Details of the landing are coming in and there are two issues to be resolved. Paolo Ferri, head of mission operations, has just confirmed that the Philae harpoons did fire but it is not known whether they are secure or not. If they have penetrated the surface, it is not yet clear how deeply they have embedded themselves.
Additionally, shortly after landing, the communications link to Rosetta began dropping and coming back online. This continues at the present time. It should have been a steady signal.
At present there is no danger perceived to the lander’s mission.
“We have no reason to think it won’t work,” says Ferri, “but we have no understanding of why it is doing this.”
Esa and DLR technicians are working now to try to resolve these issues. In a few hours there will be an expected break in communications with the mission.
UPDATE: Subsequent analysis has shown that the harpoons did not fire, as was first thought.
I hope all will be well.A very recent post says that Philae might have ended up in candidate site B.15:29 GMT
Drilling for samples will be risky
Philae has been designed to achieve its main science objectives within its initial 60-hour battery life. When asked at the press conference what was the absolutely fundamental investigation to be performed, Jean-Pierre Bibring – lead scientist for the lander – said it was to analyse the organic molecules on the comet.
To do that, it must get samples into its PTOLEMY, COSAC and CIVA instruments. There are two ways to do this: by sniffing and drilling. Sniffing involves opening the instruments and allowing molecules from the comet’s surface to drift in. The instruments are already acquiring samples like this and returning data.
Drilling is much riskier because it could topple the lander. Newton’s third law of motion says that for every action there is an equal and opposite reaction. In the minuscule gravity of the comet, any movement by Philae’s tools could cause the whole lander to shift or even take off again.
The drill turning one way will make Philae want to turn the other. Pushing down into the surface will push the lander in the opposite direction.
“We don’t want to start drilling and end the mission,” says Bibring. So they will try this only towards the end of the 60-hour nominal mission.
Someone asked that at the Rosetta blog, and this was one response:rstevenson wrote:Here's an interesting piece I just cut from the bottom right corner of the hi-res version of that picture. I think the full image is a combination of two others, so maybe this is an artifact of that combination. Perhaps it's just a coincidental alignment of comet stuff. Alternatively, it might be a bit of cable from the attempted harpooning. It seems to be casting a shadow angling off a little to the right of the longer of the lines.
Rob
idjles says:
13/11/2014 at 13:21
That looks to me like CONSERT (COmet Nucleus Sounding Experiment by Radiowave Transmission), not the harpoon, in which case the is the "forwards" leg that was facing away from Rosetta the last 10 years. Wikipedia
http://blogs.esa.int/rosetta/2014/11/13 ... th-a-view/
COMET WITH A VIEW
13 November 2014
Here is the first panoramic ‘postcard’ from the surface of a comet, returned by Rosetta’s lander Philae, which is currently on the surface of Comet 67P/Churyumov-Gerasimenko:
Yup. Solved! Here's an explanatory image shared by Pedro Contreras of Columbia...MargaritaMc wrote:Someone asked that at the Rosetta blog, and this was one response:rstevenson wrote:Here's an interesting piece I just cut from the bottom right corner of the hi-res version of that picture. I think the full image is a combination of two others, so maybe this is an artifact of that combination. Perhaps it's just a coincidental alignment of comet stuff. Alternatively, it might be a bit of cable from the attempted harpooning. It seems to be casting a shadow angling off a little to the right of the longer of the lines.
Robidjles says:
13/11/2014 at 13:21
That looks to me like CONSERT (COmet Nucleus Sounding Experiment by Radiowave Transmission), not the harpoon, in which case the is the "forwards" leg that was facing away from Rosetta the last 10 years.
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Wikipedia
That means that the whole thing, craft, lander and fuel, weigh less than many a light aircraft..." How big is the spacecraft?
The spacecraft dimensions are 2.8 x 2.1 x 2.0 metres. There are two 14-metre-long solar panels with a total area of 64 square metres. From tip to tip, the spacecraft spans 32 metres.
[ 2.8 metres is just over 9 feet. Apart from its solar panels, Rosetta would fit into our living room with space to spare!]
Rosetta's total launch mass is 3,000 kilograms. The spacecraft carries 1,670 kilograms of propellant and the lander weighs 100 kilograms."
I think it's also viewable via the ESA YouTube channelRosetta mission: Results from comet landing: 14 Nov, 13:00 GMT
Update on the Rosetta mission, including status of the Philae lander.
Hosted by Emily Baldwin - ESA Science Editor, with:
Andreas Accomazzo - ESA Rosetta Flight Director, ESOC
Stephan Ulamec - Philae Lander Manager, DLR
Matt Taylor - Rosetta Project Scientist, ESA
Philippe Gaudon - CNES Rosetta Project Manager, SONC
Holger Sierks - PI for OSIRIS, Max-Planck-Institute for Solar System Research
Valentina Lommatsch - DLR-Lander Control Center, mission team
(or Tilman Spohn - DLR-Lander Control Center, mission team)
A representative from NASA is also expected to join.
Good info from Rob!rstevenson wrote:In case you're wondering how to quickly compare those GMT times to your local time, type into Google "what time is it here in GMT" and it pops up the GMT time for your location. I tried it it here at 9:03am and it replied 1:03pm, so there's a four hour difference. So I can quickly subtract 4 hours from the times in that post above, and see that they were posted at 7:10 and 8:18am my time.
Rob
They mass less. On Earth they weighed less than a light aircraft. Currently, they weigh less than hobby model aircraft.MargaritaMc wrote:That means that the whole thing, craft, lander and fuel, weigh less than many a light aircraft...
Fixed it!Chris Peterson wrote:They mass less. On Earth they weighed less than a light aircraft. Currently, they weigh less than hobby model aircraft.MargaritaMc wrote:That means that the whole thing, craft, lander and fuel, weigh weighed less when on Earth than many a light aircraft weighs when on Earth...
