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Sep 26 2014 07:06pm
and here is another:



Rosetta's navigation camera (NAVCAM) took this image of Comet 67P/Churyumov-Gerasimenko on 21 September, from a distance of 27.8 km from the comet centre. The image covers an area of about 2 x 1.9 km and focuses on the smaller of the two comet lobes. The primary landing site J is 'above' the distinctive depression in this view

to see where it fits in, let me repeat an earlier image:

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Sep 27 2014 05:50pm
and now for the news, from http://www.esa.int/Our_Activities/Space_Science/Rosetta/Rosetta_to_deploy_lander_on_12_November

The European Space Agency’s Rosetta mission will deploy its lander, Philae, to the surface of Comet 67P/Churyumov–Gerasimenko on 12 November.
...
Over the last two weeks, the flight dynamics and operations teams at ESA have been making a detailed analysis of flight trajectories and timings for Rosetta to deliver the lander at the earliest possible opportunity.
Two robust landing scenarios have been identified, one for the primary site and one for the backup. Both anticipate separation and landing on 12 November.
For the primary landing scenario, targeting Site J, Rosetta will release Philae at 08:35 GMT/09:35 CET at a distance of 22.5 km from the centre of the comet, landing about seven hours later. The one-way signal travel time between Rosetta and Earth on 12 November is 28 minutes 20 seconds, meaning that confirmation of the landing will arrive at Earth ground stations at around 16:00 GMT/17:00 CET.
If a decision is made to use the backup Site C, separation will occur at 13:04 GMT/14:04 CET, 12.5 km from the centre of the comet. Landing will occur about four hours later, with confirmation on Earth at around 17:30 GMT/18:30 CET. The timings are subject to uncertainties of several minutes.
Final confirmation of the primary landing site and its landing scenario will be made on 14 October
...
A competition for the public to name the primary landing site will also be announced during the week of 14 October.
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Oct 2 2014 07:13am
Finally a new picture and getting closer to the comet:



Four-image montage comprising images taken by Rosetta's navigation camera on 26 September from a distance of 26.3 km from Comet 67P/Churyumov-Gerasimenko. The comet nucleus is about 4 km across.
The image shows the spectacular region of activity at the 'neck' of 67P/C-G. This is the product of ices sublimating and gases escaping from inside the comet, carrying streams of dust out into space.


and some additional information:

As the comet gets progressively closer to the Sun along its orbit, the surface will become warmer, and the level of activity will increase, producing a vast coma around the nucleus, along with a tail. It’s perhaps hard to believe looking at images like this at less than 30 km distance from the surface, but recent ground-based images have revealed that 67P/C-G’s coma already extends at least 19 000 km from the nucleus!
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Oct 4 2014 09:22am
Finally some more detailed information is coming forward:



Comet 67P/Churyumov-Gerasimenko's dimensions, as measured from images taken by Rosetta's OSIRIS imaging system. The images shown in the graphic were taken by Rosetta's navigation camera on 19 August.

Further data (indicating the key instrument used):

Dimensions (small lobe) 2.5 x 2.5 x 2.0 km OSIRIS
Dimensions (large lobe) 4.1 x 3.2 x 1.3 km OSIRIS
Rotation 12.4043 hours OSIRIS
(if you want to read more details on that -> http://www.aanda.org/articles/aa/abs/2014/09/aa24590-14/aa24590-14.html)
Spin axis Right ascension: 69 degrees; Declination: 64 degrees OSIRIS
Mass 10^13 kg RSI
(first estimate based on data available, accurate to within +-10%)
Volume 25 km^3 OSIRIS
Density 0.4 g/cm^3 RSI / OSIRIS
Water vapour production rate 300 ml/sec (Jun 2014); 1–5 l/sec (Jul-Aug 2014) MIRO
(details -> http://blogs.esa.int/rosetta/2014/09/15/miro-bathes-in-water-vapour/)
Surface temperature 205–230K (Jul-Aug 2014) VIRTIS
Subsurface temperature 30–160K (Aug 2014) MIRO
Gases detected Water, carbon monoxide, carbon dioxide, ammonia, methane, methanol ROSINA
Dust grains A few tens of microns to a few hundreds of microns COSIMA (detections also by GIADA)
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Oct 7 2014 03:58am
And now we are getting images from a closer distance:



Four-image montage comprising images taken by Rosetta's navigation camera on 30 September from a distance of 18.1 km from the centre of Comet 67P/Churyumov-Gerasimenko. Each of the four frames making up the montage measures about 1.4 kilometres across. The image features Site J, the primary landing site for Rosetta’s lander Philae.
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Oct 9 2014 07:37am


Four-image montage comprising images taken by Rosetta's navigation camera on 2 October from a distance of 19 km from the centre of Comet 67P/Churyumov-Gerasimenko. The image scale is 1.45 metres/pixel, so each 1024 x 1024 pixel frame making up the montage is about 1.5 km square.
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Oct 9 2014 10:07pm


This image of the surface of Comet 67P/Churyumov-Gerasimenko was taken by Rosetta’s OSIRIS narrow-angle camera on 19 September 2014, from a distance of 28.5 km.
The image features a large boulder casting a long shadow on the surface of the comet. The boulder has a maximum dimension of about 45 metres and is the largest structure within a group of boulders located on the lower side of the comet’s larger lobe. This cluster of boulders reminded scientists of the famous pyramids at Giza near Cairo in Egypt, and thus it has been named Cheops for the largest of those pyramids, the Great Pyramid, which was built as a tomb for the pharaoh Cheops (also known as Kheops or Khufu) around 2550 BC.
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Oct 10 2014 12:13am
Beautiful photos.
November 12th, gonna be a good day :D
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Oct 10 2014 05:53am
Quote (ringo794 @ 10 Oct 2014 06:13)
Beautiful photos.
November 12th, gonna be a good day :D


while not from comet-67p, the rosetta team has released a few more images associated with the lutetia fly-by, here are two of them:



Looking face on at the North Pole Crater Cluster (purple outline) on asteroid Lutetia, with Massilia to the lower left (red outline). Marked on the image are the concentric grooves or ‘lineaments’ associated with the large craters. The lineaments coloured blue infer the presence of a large crater – nicknamed Suspicio – on the unseen portion of Lutetia. Yellow denotes lineaments not associated with any of the craters discussed in this study.
Lutetia was imaged in July 2010 by ESA’s Rosetta spacecraft, while en route to Comet 67P/Churyumov-Gerasimenko. Rosetta took images of the 100 km-wide asteroid for about two hours during the flyby. At its closest approach, Rosetta was 3162 km from Lutetia. In the image shown here, north is towards the observer.




The inferred location of Suspicio crater on the unseen southern hemisphere of asteroid Lutetia (marked in blue). The hidden crater could be up to 45 km in diameter – the blue outlines correspond to diameter estimates of 15, 30 and 45 km, respectively. The crater is inferred based on the numerous grooves or ‘lineaments’ seen concentric to the crater in the northern hemisphere of the asteroid. There are no image data available for this side of the asteroid, as can be inferred from the blank shape model.
Lutetia was imaged in July 2010 by ESA’s Rosetta spacecraft, while en route to Comet 67P/Churyumov-Gerasimenko. Rosetta took images of the 100 km-wide asteroid for about two hours during the flyby. At its closest approach, Rosetta was 3162 km from Lutetia. In the image shown here, north is up.
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Oct 11 2014 07:34am
Back to comet-67p:



Four-image montage comprising images taken by Rosetta's navigation camera on 8 October from a distance of 16.9 km from the centre of Comet 67P/Churyumov-Gerasimenko. The image scale is about 1.25 metres/pixel, so each 1024 x 1024 pixel frame making up the montage is nearly 1.3 km square.

and

The montage has been rotated 90 degrees clockwise to place the region containing Cheops at the top for emphasis; ...
When seen in this side-on view, Cheops appears much more like its Egyptian pyramid namesake and has a height of approximately 25 metres, compared with a width of 45 metres as seen from above in yesterday’s OSIRIS image. For reference, the real Pyramid of Cheops at Giza is 139 metres high and 230 metres across at the base.
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