It looks like NASA's hard-working
Opportunity Rover
nabbed our very first pictures of a comet seen from another world! A study of
raw images
taken by the rover turned up a very promising fuzzy object. Only three night sky pictures were posted today, but two clearly show a fuzzy spot near the center of the field. Stars show as points of light and there are what appear to be a smattering of cosmic ray hits, but in the photo above, the brightest object is slightly elongated (trailed during the exposure?) and cometary in appearance.
Here's another photo:
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A second picture from Opportunity possibly showing the comet. Click for original. Credit: NASA/JPL-Caltech[/caption]
Looking back over
earlier photos
of the sky taken on Sol 3212 show only stars and no fuzzy blobs. The pictures were taken around 4:13 a.m. local time with the Sun 25 degrees below the horizon. Opportunity can photograph diffuse objects as dim as the Andromeda Galaxy at magnitude +3.5 and stars down to magnitude +6 or +7. That's similar to what we see on Earth on very dark night. Since the comet glowed far brighter at around magnitude -5 by some estimates, it would be a relatively easy catch for the rover panoramic camera.
[caption id="attachment_115467" align="aligncenter" width="580"]
Curiousity Navcam photo of the sky on October 19, 2014, shows the silhouetted rim of Gale Crater and lots of noise. Credit: NASA/JPL-Caltech[/caption]
NASA has also posted images taken by the Curiosity Rover but for the life of me I can't find any sign of the Comet Siding Spring. Maybe it'll pop out after the noise is removed. We'll keep you posted.
[caption id="attachment_115468" align="aligncenter" width="580"]
Another Curiosity photo of the sky. If you look closely you'll see stars among the noise. Click for original Credit: NASA/JPL-Caltech[/caption]