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Comets

Very long article:

Rosetta: 'Goosebumps' on 'space duck' hint at comet formation
By Jonathan Amos Science correspondent, BBC News

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A fascinating texture: Comet 67P's "goosebumps" have a preferred scale of about 3m

Scientists working on Europe's Rosetta probe, which is tracking Comet 67P, say they may have found evidence for how such icy objects were formed.
New pictures of the surface reveal a lumpy texture in places that researchers speculate could have been the body's original building blocks.
Their appearance means they are being dubbed "goosebumps", which is a bit of fun given the comet's duck-like shape. :)

But if this interpretation is correct, it represents a major discovery.
"We still have to model this, but I think they really could be pointing back in time to the early days of the Solar System - to the formation of the building blocks of cometary nuclei," said imaging team leader Holger Sierks from the Max-Planck-Institute for Solar System Research in Göttingen, Germany.
"Our thinking is that accreting gas and dust would have formed little 'pebbles' at first that grew and grew until they got up to the size of these goosebumps - about 3m in size - and for whatever reason, they couldn't then grow any further.
"Eventually, they'd have found a region of instability and clumped together to form the nucleus," he told BBC News.

Rosetta team-member Stephen Lowry said the goosebumps (which to some also look like a clutch of "dinosaur eggs") were among the most startling results to have come out of the mission so far.

etc...

http://www.bbc.co.uk/news/science-environment-30931445
 
Lovejoy is apparently at magnitude 4, but closer to Perseus than Taurus. But now it's nearly 54 degrees of altitude, too high for my bins! :(
 
We've been enjoying splendid views of Lovejoy these past clear, moonless nights. No tail to speak of, but a lovely little fuzzball in binoculars. There is supposed to be a similarly bright comet, Catalina, visible in the northern hemisphere this coming December. Better luck with that one, rynner!
 
I saw Lovejoy yesterday, just before the Moon moved too close. A couple of degrees above 39 Arietis. Don't suppose it will be visible now until the Moon moves away, if then.
 
Is it just me that wonders how long we have before someone 3D prints scale models of 67P and sells them as butt plugs?
 
Is it just me that wonders how long we have before someone 3D prints scale models of 67P and sells them as butt plugs?
Hopefully just you, but if it hasn't been done yet I suppose you've got yourself a business opportunity? o_O
 
67p? That's very cheap! Is it used?
 
Controllers now banking on Philae wake-up call
By Jonathan Amos Science correspondent, BBC News
The European Space Agency (Esa) says it will conduct no more dedicated searches for its lost comet lander.

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Esa has released the full image sequence of Philae moving away from its Rosetta mothership on 12 November, en route to the surface of 67P

The Philae probe made its historic touchdown on the 4km-wide "icy dirtball" 67P in November, but rapidly went silent when its battery ran flat.
High-resolution pictures of the surface of the comet acquired by the orbiting Rosetta satellite have failed to identify the lander's location.
Controllers say they will simply wait now for Philae itself to call home.
They will begin listening in a few weeks' time with the hope that communications could be established in the May/June timeframe.
This would be when improved lighting conditions at the probe's presumed resting place provide enough power to run the onboard radio transmitter.

Esa on Friday released the full image sequence of the washing-machine-sized Philae drifting away from Rosetta at the start of November's descent to 67P.
Previously, only a few frames of this picture series had been made public.

Researchers have a good idea of where the robot went subsequently. On touchdown, it bounced twice, crossing a large depression named "Hatmehit", before coming to rest in a dark ditch that has now been dubbed "Abydos".
This much is clear from the pictures Philae took of its own surroundings. And this final resting place, the mission team believes, is just off the top of the "head" of the duck-shaped comet.

Data from a radio experiment running on the probe at the time of its shutdown suggests it should be found somewhere in a strip of terrain roughly 350m by 30m.
Rosetta photographed this general location on 12, 13 and 14 December, with each image then scanned by eye for any bright pixels that might be Philae. But no positive detection was made.
"Actually, we've seen several Philaes!" commented Stephan Ulamec, the lander manager at the German Space Agency (DLR). "And that's the problem: it's very difficult to distinguish Philae from surface features that resemble a little bit the shape of the lander."
Dr Ulamec said consideration was given to bringing in military imaging experts to help with the analysis, but it was concluded that looking for probes on comets was a very different task to hunting for camouflaged tanks.

Esa plans now no further specific imaging searches. The comet, which is getting ever closer to the Sun (current distance is 364 million km), is expected very shortly to become much more active.
The warmth of our star will vaporise 67P's ices, generating huge jets of gas and dust in the process.
These jets make it harder to control Rosetta. Already, it has retreated from the 20km separation distance it was holding in December, and is now circling in a 30km-high orbit.
There is a plan to make a very close flyby on 14 February, which would see Rosetta sweep just 6km above the surface, but this will be a quick in-and-out pass that will go across the underside of the duck's body - far away from Philae's presumed resting place.

Controllers are banking on Philae itself making its position known.
This should happen as the comet's southern hemisphere comes out of winter in the coming weeks. Lighting conditions in the ditch will then get more intense, enabling the probe to first boot-up and then to communicate with Rosetta.
The routine will see Rosetta call out and listen for a reply. Initially, the energy needed to fire up its transmitter to make the response will see Philae fall straight back to sleep.

But in time, it should be gathering enough light on its solar panels to maintain a stable telecoms link and start to warm and charge the battery system as well.
This would see Philae resuming the science observations that were closed down just 60 hours after landing in November. As luck would have it, this might happen around August when the comet will be closest to the Sun (perihelion) and in its most active phase.
"There is good confidence, and of course all the teams are getting prepared for various scenarios," Dr Ulamec told BBC News. "It may be that they only get very limited periods of operation in the [dark] pocket, and they will have to plan for more modest science sequences."

Everyone must hope that Philae is not damaged by the cold that grips its position. Its electronics may be experiencing temperatures of minus 80C. That is some 20 degrees below the qualification limit set by the manufacturers. Thermal tension could start to loosen soldered joints. But good engineering requires large margins, so Philae should be safe.

http://www.bbc.co.uk/news/science-environment-30931443

More pics on page!
 
Rosetta catches its own shadow
By Jonathan Amos BBC Science Correspondent

The highest resolution image yet taken of Comet 67P by the Rosetta satellite has just been released.
It was acquired during the Valentine's Day flyby when the European Space Agency probe passed just 6km from the surface of the "icy dirtball".
The view, which shows the detail in features down to 11cm, is of a region on the bottom of the "space duck".
With the Sun directly behind Rosetta, it is just possible to see a shadow of the satellite itself on the surface.

"I like it because you get this nice juxtaposition of Rosetta against the alien landscape," said Dr Matt Taylor, the mission's project scientist.
The precise location of the image has been worked out to be on the boundary of two regions known as Imhotep and Ash.

67P is now getting more and more active as it moves closer to the Sun, meaning it is no longer possible for the European probe to work continuously at close-quarters, as was the case through the back end of last year.
The stream of gas and dust coming away from the comet produces drag on the spacecraft, complicating the job of the controllers who must drive Rosetta through space.
The plan instead is to sit back from 67P and make the occasional close-in approach. The 14 February pass was just such a manoeuvre.

etc...

http://www.bbc.co.uk/news/science-environment-31694195
 
One of the surprising facts in the above BBC article about Comet 67P is that "It is 70-80% empty space".
 
20 March 2015 Last updated at 16:16
Rosetta's comet is spinning down
By Jonathan Amos Science Correspondent

The comet being observed by Europe's Rosetta satellite is very gradually spinning down.
The icy dirt-ball takes 12.4 hours to complete one rotation, but mission controllers have noticed that this is extending by about a second a day.
And this rate of change is increasing as Comet 67P gets more active.
"The gas jets coming out of the comet - they are acting like thrusters and are slowing down the comet," said flight director Andrea Accomazzo.

The European Space Agency official was speaking this week at the Royal Aeronautical Society in London.
He was describing how his team has learnt to fly Rosetta around the 10-billion-tonne, 4km-wide body with remarkable precision.
Navigators use a system of landmarks on the comet to understand how it is rotating and moving through space.
This information is fed into a model that helps plan a trajectory for the satellite.
And it was while running this model that the Esa team realised the landmarks were not quite turning up in the right place at the expected time.

In September last year, it was determined that the rotation period was extending by 33 milliseconds per day. Now, with the comet moving closer to the Sun and throwing out much larger volumes of gas and dust, this spin-down effect is approaching a second a day.

etc...

http://www.bbc.co.uk/news/science-environment-31965458
 
Next, it will start decelerating and laying in a course for Earth...
'Rendezvous With Rama' spring to mind?
 
Controllers now banking on Philae wake-up call
By Jonathan Amos Science correspondent, BBC News
The European Space Agency (Esa) says it will conduct no more dedicated searches for its lost comet lander.

http://www.bbc.co.uk/news/science-environment-30931443

And so, with the sun above the yard-arm, it came to pass...
Philae comet lander wakes up
14 June 2015

The European Space Agency (Esa) says its comet lander, Philae, has woken up and contacted Earth.
Philae, the first spacecraft to land on a comet, was dropped on to the surface of Comet 67P by its mothership, Rosetta, last November.
It worked for 60 hours before its solar-powered battery ran flat.

The comet has since moved nearer to the sun and Philae has enough power to work again, says the BBC's science correspondent Jonathan Amos.
The probe tweeted the message, "Hello Earth! Can you hear me?"
On its blog, Esa said that Philae contacted Earth, via Rosetta, for 85 seconds in the first contact since going into hibernation in November.
"Philae is doing very well. It has an operating temperature of -35C and has 24 watts available," said Philae project manager Stephan Ulamec.
Scientists say they now waiting for the next contact.
-----------------------------------------------------------

Analysis: Jonathan Amos, BBC science correspondent
When Philae first sent back images of its landing location, researchers could see it was in a dark ditch. The Sun was obscured by a high wall, limiting the amount of light that could reach the robot's solar panels. Scientists knew they only had a limited amount of time - about 60 hours - to gather data before the robot's battery ran flat.

But the calculations also indicated that Philae's mission might not be over for good when the juice did eventually run dry. The comet is currently moving in towards the Sun, and the intensity of light falling on Philae, engineers suggested, could be sufficient in time to re-boot the machine.

And so it has proved. There is some relief also, because the very low temperatures endured by the lander in recent months could have done irreparable damage to some of the circuitry. The fact that both the computer and transmitter have fired up indicate that the engineering has stood up remarkably well to what must have been really quite extreme conditions. Scientists must now hope they can get enough power into Philae to carry out a full range of experiments.
One ambition not fulfilled before the robot went to sleep was to try to drill into the comet, to examine its chemical make-up. This will become a priority.

...

http://www.bbc.co.uk/news/science-environment-33126885
 
I've just come here to post the same thing :)
 
Controllers wait on Philae link
By Jonathan Amos BBC Science Correspondent, Le Bourget

No new signals have been picked up from the Philae comet lander since a brief radio contact on Sunday.
European Space Agency (Esa) controllers listened again on Tuesday night but heard nothing.
This was not surprising, they said, given the less than ideal conditions for a radio connection.

Philae called home from Comet 67P on Saturday, its first contact since running out of battery power shortly after landing some seven months ago.
The communication was short - just 85 seconds - and was then followed by an even briefer link-up on Sunday.
The robot’s mothership Rosetta, which dropped the robot on to the 4km-wide icy dirt-ball, is now being moved closer to facilitate a more effective relay.
Currently, the satellite is sitting back from the comet at a distance just above 200km.
Controllers have commanded Rosetta to get as close as 180km. They have also told the probe to keep its antenna pointing directly down to aid a stronger radio connection.

The mission has to be cautious, though. Comet 67P is throwing huge quantities of gas and dust into space as its ices melt in the warmth of the Sun.
If controllers are not careful, this blizzard of material will confuse Rosetta’s navigation systems, potentially tripping the probe into a protective “safe mode” that shuts down all but essential functions.

This would make communication with Philae impossible but also risk putting Rosetta in some danger because it would no longer be under full control.
“It’s like flying your car in a snowstorm. You don’t see anything, and that’s quite dangerous,” said Elsa Montagnon, Esa’s Rosetta deputy flight director.
“It’s the same for Rosetta. Its 'eyes' – its star-trackers, which it uses for autonomous orientation - rely on finding stable star patterns that they can follow.
“And in this very dusty environment, the trackers can mistake dust particles sometimes for stars and that can lead the spacecraft in the wrong direction.”

etc...

http://www.bbc.co.uk/news/science-environment-33163835
 
Comet lander Philae renews contact
By Jonathan AmosBBC Science Correspondent
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Philae's telemetry was passed to controllers in Darmstadt, Germany
Europe's Philae comet lander has been back in touch with Earth - its first contact since Sunday night (GMT).

The communication was relayed by its mothership Rosetta, which is in orbit around the 4km-wide icy dirt-ball known as 67P/Churyumov-Gerasimenko.

The signal was picked up by the US space agency's huge Goldstone antenna in California and then passed to the European Space Agency in Germany.

Before last weekend, Philae had been in hibernation for seven months.

The robot lost power just 60 hours after landing on the comet on 12 November - the consequence of bouncing into a ditch where sunlight could not reach its solar panels to generate electricity.

With the comet now having moved substantially closer to the Sun, the illumination conditions have improved and Philae has come back to life.

The communications with Earth - over a distance of 305 million km - have so far been very short, lasting just a matter of a few tens of seconds. A first contact came on Saturday; a second was received on Sunday. Friday's is also very brief - two individual connections lasting two minutes each.

This is long enough to glean the health status of Philae, which appears to be good.

"We are very happy to have received signals from the lander again, and we are all working hard towards establishing a robust link between Rosetta and Philae," commented Patrick Martin, Esa's Rosetta mission manager.

Controllers are currently in the process of manoeuvring Rosetta closer to the comet to try to establish longer and more robust connections. This will see the separation brought down to about 180km..

In time, it should be possible for Philae to resume the science investigations of Comet 67P that were terminated when the power went down.

The key experiment is to drill into the icy body, to determine its chemical make-up.

This was tried during November's 60-hour operating window but failed to produce a result, probably because the posture of the robot meant that the drill tool did not manage to touch any surface material.

Engineers think that if they can command Philae to rotate itself in the coming weeks, it ought then to be possible to recover a sample. But this all depends on the power levels available to Philae in its shaded location.

There are concerns also for the mothership Rosetta. It has only recently retreated from 67P to try to keep clear of all the gas and dust now coming off the comet as it warms up on its journey in towards the Sun.

This blizzard of material has the potential to confuse Rosetta's automated navigation systems, and controllers must take care that they do not put the probe in harm's way as they work on building a better radio link with Philae.

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On its historic landing in November, Philae did not make the graceful touchdown depicted here

http://www.bbc.co.uk/news/science-environment-33206661
 
Good news, everybody!
 
Philae probe still talking to Earth from surface of comet, say Rosetta scientists
Solar-powered lander now getting enough sunlight to send periodic transmissions and charge batteries so it can continue to work through the night



Artist’s impression issued by the European Space Agency of the Rosetta’s lander Philae on the surface of comet 67P/Churyumov-Gerasimenko. Photograph: ESA/PA

Saturday 20 June 2015 04.03 BSTLast modified on Saturday 20 June 201504.14 BST
  • Europe’s robot lab Philae phoned home on Friday after several days’ silence in its journey towards the sun on the back of a comet and is “doing very well”, the German Aerospace Centre (DLR) said.

The latest contact lasted 19 minutes and is the third time Philae has touched base with Earth since it landed on Comet 67P/Churyumov-Gerasimenko on 12 November after piggybacking on its mothership Rosetta.

The mission seeks to unlock the long-held secrets of comets – primordial clusters of ice and dust scientists believe may reveal how the solar system was formed.

After landing on the comet, Philae had used its stored battery power to send home reams of data before going into standby mode.

The hope was as the comet approaches the sun, solar energy would recharge Philae’s batteries enough for it to reboot, make contact and ultimately resume scientific work.

It took seven months before Philae woke from hibernation on 13 June and made contact with Earth for two minutes. It reported back again two days later.

On Friday, Philae transmitted 185 data packets back to Earth between.

“Among other things, we have received updated status information,” Michael Maibaum, a systems engineer at the DLR Lander Control Centre in Cologne.

“At present, the lander is operating at a temperature of zero degrees Celsius, which means that the battery is now warm enough to store energy. This means that Philae will also be able to work during the comet’s night, regardless of solar illumination.”

The data transmitted also shows the amount of sunlight available had increased.

“More solar panels were illuminated; at the end of contact four of Philae’s panels were receiving energy,” said the DLR statement.

“The contact has confirmed that Philae is doing very well.”

http://www.theguardian.com/science/...-from-surface-of-comet-say-rosetta-scientists
 
Rosetta's 'rubber duck' comet was once two objects
By Jonathan Amos BBC Science Correspondent

The rubber duck-shaped comet being followed by Europe's Rosetta probe used to be two separate objects.
Scientists say pictures of 67P show its two lobes to have "onion skin" layers that intersect in a way that can only be the result of two different bodies having collided and stuck together.

Ever since Rosetta arrived at the comet, the origin of its bizarre form has been one of the major puzzles.
The solution is now due to be published in the journal Nature.
Mission team members have also held a media conference to give further details, at the European Planetary Science Congress in Nantes, France.

Rosetta first spied the duck on approach to 67P/Churyumov-Gerasimenko in July 2014.
The idea that it was a "contact binary" - two conjoined comets - was a popular explanation from the word go.
But proving it has not been straightforward. An alternative possibility is simply that the icy dirt ball has been sculpted this way.
Every time it comes around the Sun, 67P's ices warm and it throws off gas and dust, and it could have been that this process has dominated in just one region to produce the distinctive appearance.

The Osiris camera on Rosetta can now settle the debate.
It reveals layers up to 650m thick in the body of the duck that are independent of similar strata detected in its head.
Additional measurements taken by Rosetta of variations in the local tug of gravity across the lobes also support this two-body origin.
The direction of the tugging is more closely aligned with the independent layering than with a centre of mass associated with a single object.

Scientists say that to collide and stick together, the impact must have been a very low velocity one - perhaps just a few metres per second. Any faster, and the primary objects would have done enormous damage to each other.
"I would say it's a quite beautiful love story," Matteo Massironi, from the Osiris team, said at Monday's press briefing.

etc...

http://www.bbc.co.uk/news/science-environment-34379287
 
Surprise discovery suggests 'gentle' start for Solar System
By Pallab Ghosh Science correspondent, BBC News

The Rosetta spacecraft has discovered molecular oxygen in the cloud of gas surrounding the comet it is tracking.
The discovery has come as a complete surprise to scientists who thought that oxygen would have reacted with other elements as planets were forming.
The results indicate that current ideas about how our Solar System formed may be wrong.
The study has been published in the journal, Nature.

Researchers used Rosetta's Rosina instrument to "sniff" the atmosphere around Comet 67P/Churyumov-Gerasimenko, as the probe trailed the icy body over a six-month period.
They found that free oxygen was the fourth most common gas around the comet, after water vapour, carbon monoxide and carbon dioxide.

One of the scientists involved, Professor Kathrin Altwegg of Bern University said that the scientists involved in the study thought the result was a mistake when they first saw the data.
"When we first saw it, we went a little bit into denial because it is not what you would expect to find on a comet," she said.

That is because oxygen reacts very easily with other elements to form compounds, rather than stay in its unique form. The researchers suggest that oxygen must have been frozen very quickly and became trapped in clumps of material early on in the formation of the Solar System.
"It was the most surprising discovery we have made so far (about the comet)," said Prof Altwegg. "The big question was how it got there".

Many current theories of how the planets and comets formed around the Sun suggest a violent process that would have heated up the frozen oxygen - which would then have reacted with other elements.

The suggestion is that the Solar System formation must have been an altogether quieter affair.
"If we have O2 at the beginning of the formation of the comet, how did it survive so long?" said the study's author Andre Bieler, from the University of Michigan.
"All the models say it shouldn't survive for so long, which tells us something about the building of our Solar System - it has to be very gentle to build these ice grains, it seems it is a pretty pristine material still.
"Now we have evidence that this significant part of this comet has in fact survived the formation of our Solar System."

...

http://www.bbc.co.uk/news/science-environment-34660576
 
Booze and sweets officially found in nearby comet for first time

Future travellers to a comet might not need to pack beer or sweets. Two of our favourite vices – alcohol and sugar – are already present on at least one comet in our neighbourhood.
Comet C/2014 Q2, also called comet Lovejoy, made its closest approach to the sun in January this year, becoming visible to the naked eye and also giving astronomers the chance to study the make-up of its atmosphere.

Nicolas Biver and colleagues at the Paris Observatory used the Institut de Radioastronomie Millimétrique (IRAM) 30-metre radio telescope in Sierra Nevada, Spain, to observe the comet when it was at its brightest.

The telescope picked up the signatures of 21 compounds, including organic molecules such as ethylene glycol, formic acid and acetaldehyde that have been detected before on Hale-Bopp and other comets. It also found ethanol and glycolaldehyde, a simple sugar molecule.

The researchers say it’s the first time these substances have been detected on a comet. But scientists who have studied data from the Rosetta mission, which has been orbiting comet 67P/Churyumov-Gerasimenko for over a year, quibble a bit: they’ve seen it too. Rosetta detected ethanol on comet 67P, although the finding has not yet been published. Glycolaldehyde was detected by the mass spectrometer on board the Philae lander.

Comets contain samples of some of the oldest material in the solar system, and can therefore tell us about how planets were formed in our sun’s youth.

Comets smashing into Earth early in our planet’s history might even have brought the raw materials for life. The organic compounds we find on comets are a start, but more complex molecules could have been created during impact.

“The detection of these compounds in comets helps to expand our knowledge of… the potential ingredients for life that could have been delivered to the early Earth or other planetary surfaces by comets,” says Jamie Elsila, an astrochemist at NASA. “This knowledge can then help evaluate the likelihood of potential pathways to life.”

etc...

https://www.newscientist.com/articl...m=NLC&utm_source=NSNS&utm_content=NewTemplate
 
Rosetta probe to 'crash land' on comet at end of its mission but spacecraft will make a softer touch down on 67P than its ill-fated Philae lander
By Sarah Griffiths for MailOnline
Updated: 15:39, 4 November 2015

The Rosetta probe may be sent crashing into the distant comet it has been orbiting at the end of its lifetime next September.
But the spacecraft is expected to have a far softer landing than its ill-fated Philae lander, which bounced uncontrollably across the surface of the duck-shaped comet 67P.
Instead it will approach the comet slowly, beaming back as much information as possible to scientists on Earth in its dying moments.
Experts say the orbiter's final moments may ultimately provide more data and clearer pictures than were possible with the Philae lander.

The fate of the European Space Agency's (ESA) Rosetta has been discussed for over a year and is yet to be completely decided, with a possibility remaining that the spacecraft could land on the comet's surface to hibernate.
Rosetta project scientist Matt Taylor said: 'The crash landing gives us the best scientific end-of-mission that we can hope for.'

But such a destructive end will be emotional for scientists, some of whom have worked on the mission since it began in 2003, Nature.com reported.
'There will be a lot of tears,' Taylor said.
He has previously told Space Exploration Network: 'I feel from a "personal" perspective, there is something rather fitting in putting Rosetta down on the surface, re-uniting it with Philae.'

It took a decade for the Rosetta orbiter to reach comet 67P/Churyumov-Gerasimenko in deep space, having launched in 2004.
The Philae lander was dropped onto its surface on 12 November 2004 but Esa has not heard from it since July.

Meanwhile, Rosetta is surveying the comet from its orbit, but the mission will have to come to an end when Rosetta runs out of fuel, power and funding in September.
Because of this, some experts have proposed to Esa that the craft should die in a 'blaze' of glory.
The favoured plan for ending the mission, however, is to crash the craft very slowly into the comet.

Rosetta has more powerful sensors on board than Philae, so a slow descent would mean it could gather more data and better pictures of the comet's surface.
Once it gets within two-and-a-half miles (4km) for example, it could distinguish between gases emerging from two lobes of the comet to shed light on how the rocky body varies in its composition.

Mission manager Patrick Martin said current plans would see Rosetta spiral down to five miles (8km) of 67P's surface in August – the closest it's come so far – before gradually getting closer as it orbits the comet and finally crashing gently a month later.
But this could change.
Flight director Andrea Accomazzo has previously said that it would be ideal if Rosetta could land and hibernate on the comet, waiting to approach the sun in four or five years' time.
However, he said the cold of deep space would probably damage the craft in that time, and it wouldn't have enough fuel to function.

A crash landing would be more complicated than it seems.
In order to send images and data back to Earth, engineers would have to design the craft's final descent in a way that it crash lands on the comet's Earth-facing side.

Because 67P is an irregular shape, navigating close to its surface will be difficult too.

Spacecraft-operations manager Sylvain Lodiot said that once Rosetta has crashed on the comet – no matter how soft the landing – there will be no way to point its antenna towards Earth and for scientists to communicate with it, or for it to angle its solar array to harvest power from the sun's rays.
'Once we touch, hit or crash, whatever you want to call it, it's game over,' he said.

Nasa recently performed a similar manoeuvre with its Messenger spacecraft, which was sent crashing into the surface of Mercury on 30 April 2015.
And on 4 July 2005, Nasa's Deep Impact spacecraft launched an impactor into the surface of the comet Tempel 1 and observed the results.
The impact released an unexpectedly large and bright cloud of dust, and also left behind a noticeable crater on the surface.

http://www.dailymail.co.uk/sciencet...softer-touch-67P-ill-fated-Philae-lander.html

Pics, etc, on page.
 
Astronomers find a tailless comet, first of its kind
Reuters
April 30, 2016

CAPE CANAVERAL, Fla. (Reuters) - Astronomers have found a first-of-its-kind tailless comet whose composition may offer clues into long-standing questions about the solar system's formation and evolution, according to research published on Friday in the journal Science Advances.

The so-called "Manx" comet, named after a breed of cats without tails, was made of rocky materials that are normally found near Earth. Most comets are made of ice and other frozen compounds and were formed in solar system's frigid far reaches.

Researchers believe the newly found comet was formed in the same region as Earth, then booted to the solar system’s backyard like a gravitational slingshot as planets jostled for position.

Scientists involved in the discovery now seek to learn how many more Manx comets exist, which could help to resolve debate over exactly how and when the solar system settled into its current configuration. ...

FULL STORY: https://www.yahoo.com/news/astronomers-tailless-comet-first-kind-135238116.html?ref=gs
 
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