Comet develops coma
The coma of Comet Churyumov–Gerasimenko grows in this series of images from Rosetta's spacecraft, taken from March 27th to May 4th.
ESA / Rosetta / MPS for OSIRIS Team MPS / UPD / LAM / IAA / SSO / INTA / UPM / DASP / IDA

Comet 67P/Churyumov-Gerasimenko is rousing.

Shown here in this series of images from the OSIRIS narrow-angle camera on ESA’s Rosetta spacecraft, the nucleus of Comet C-G is developing its dusty coma. The images were taken from March 27th to May 4th, and by the end of the sequence the coma was about 1,300 kilometers (800 miles) in radius. The coma grows as the dirty iceball bears down on the Sun, the rising temperatures evaporating carbon dioxide and water ices, as well as other volatiles, on the nucleus’s surface.

The comet’s nucleus is only 4 km across, but the coma may eventually extend hundreds of thousands of kilometers as it whips through its closest approach to the Sun in August 2015.

The Rosetta spacecraft took the last of these images from a distance of roughly 2 million kilometers as it makes its way toward the comet. The craft will rendezvous with Comet C-G this August and deploy its lander, Philae, to the nucleus’s surface in November. If all goes according to plan, the spacecraft will travel with the comet from August 2014 through perihelion, closely watching as the nucleus suffers the rising onslaught from solar heating.

Read more about the waking comet in the ESA press release. And this summer keep an eye out for our August 2014 issue, where we’ll have an in-depth article on the Rosetta mission.




Image of Thomas-Yelin


May 16, 2014 at 4:42 pm

Which globular cluster is that?



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Image of

May 20, 2014 at 12:33 am

Not sure, but based on its location and direction my guess is M75

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Image of Marc Dubbeldam

Marc Dubbeldam

May 21, 2014 at 11:05 am


Clear Skies,


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Image of John O'Dee

John O'Dee

May 19, 2014 at 8:42 pm

There is another object that moves through the frame in this 9 image gif. In the 7th image it "blinks on" near the center of the lower right quadrant. In the 8th image it's harder to catch but it had moved to the right and is near the Comet. And in the 9th image it "blinks on" to the left and slightly below center of the image. I am guessing it's a small asteroid but I'm not certain.

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