I see that the large 'crater' on the 'head' of the comet has been selected as one of five prospective landing sites ( landing site B ) for the Rosetta probe lander-Philae. This means it will receive very close scrutiny over the next couple of weeks. Perhaps this will resolve the question of whether or not it is an impact crater. The European Space Agency is now cautiously calling it 'crater-like'.
http://www.esa.int/spaceinimages/Images/2014/08/Candidate_landing_site_B

what surprises me about this photo is just it's shape . I'm surprised it's still in 1 piece you would think it would not take to much to snap the middle piece .

Let's hope they don't crash the space craft into it you never know if it exploded on impact weather it would snap in harf , if it hit it in the weakest part . It certainly looks weak in the middle bit

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It turns out that this comet is about three tenths as dense as liquid water. Given that it's supposed to be made mostly of frozen water, this would presumably have to be in the form of settled or lightly packed snow, which has the appropriate density. It doesn't seem likely that it could survive a substantial impact, intact.
Comet Borelly has a similar density. It shows no apparent cratering, though. This could mean that it's been shattered by impact, and reconsolidated, erasing signs of the impact.
Comet 67P/ Churyumov/Gerasimenko shows a number of what appear to be substantial craters. It may contain materials more resilient or resistant to impact that would be expected of snow.

They've found that the comet is surprisingly dark, about as dark as coal. No exposed ice is discerned at all, accenting this dark surface. That's hard to understand, given that faint jets of vapor have been detected leaving the nucleus. The usual understanding of how a comet works, is that it emits vapor which sublimes directly from ice exposed to the heat of the Sun.

They've found that the comet is surprisingly dark, about as dark as coal. No exposed ice is discerned at all, accenting this dark surface. That's hard to understand, given that faint jets of vapor have been detected leaving the nucleus. The usual understanding of how a comet works, is that it emits vapor which sublimes directly from ice exposed to the heat of the Sun.

Thanks Michael. This is from NASA.


The instrument, named Alice, began mapping the comet’s surface last month, recording the first far-ultraviolet light spectra of the comet’s surface. From the data, the Alice team discovered the comet is unusually dark -- darker than charcoal-black -- when viewed in ultraviolet wavelengths. Alice also detected both hydrogen and oxygen in the comet’s coma, or atmosphere.

Nothing more till November.

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A primary and backup landing site have been selected for the Philae lander, it was announced this morning. The prime site, designated 'J', but soon to have a proper name, is positioned on a relatively smooth area, near the edge of the large, crater-like feature on the 'head' lobe of the comet nucleus. It is also near two small pits which are believed to be sites of venting of volatile ices that sublime directly to gases. The article, linked below, gives more details, together with photographs of the primary landing site.
http://www.skyandtelescope.com/astronomy-news/spacecraft-and-space-missions/philae-landing-site-on-comet-67p-09152014