Comet, Dead Ahead! ESA’s Rosetta Is Only Days Away From Its Target

Comet 67P/C-G imaged by Rosetta's NAVCAM on July 31, 2014 (post-processed) — *Comet 67P/C-G imaged by Rosetta’s NAVCAM on July 31, 2014 (post-processed)*

She’s almost there! After a decade of soaring through the inner solar system ESA’s Rosetta spacecraft (and Philae lander) are now on final approach to Comet 67P/Churyumov-Gerasimenko, the ultimate goal of the mission. On August 6 the spacecraft will approach within 100 km of the comet and attempt to establish orbit — if successful, Rosetta will become the first spacecraft ever to do so!

In the meantime we are getting treated to better and better images of the comet’s 4-km-wide nucleus as Rosetta closes the gap. The picture above was taken just yesterday, July 31, with the spacecraft’s navigational camera. Details of 67P’s unexpected double-lobed contact binary shape are becoming more evident, with surface features coming into view. As we’ve discovered several times before, every comet is a unique world – and 67P is no exception! Click below for an even better view…

Rosetta’s NAVCAM is a wide-angle camera and is used for just that: navigation. But its OSIRIS instrument is made for capturing images, in both wide- and narrow-angle views – here’s a shot taken several days earlier with the OSIRIS NAC:

Comet 67P/C-G taken with OSIRIS on July 29, 2014 — *Comet 67P/C-G acquired with OSIRIS on July 29, 2014*

Check that out! The rugged terrain on 67P is even more evident in this 37m/pixel image, as are some of the bright spots and bands that had been seen previously during Rosetta’s approach.

The image above was acquired when Rosetta was about 1,200 miles (1950 km) from the comet… that’s the distance between Providence, RI and Miami! Pretty impressive telephoto, I’d say! 🙂

As Rosetta approaches 67P it can begin to put more of its scientific instruments to work. Just today it was announced that temperatures of the comet’s nucleus have been acquired with Rosett’as visible, infrared and thermal imaging spectrometer (VIRTIS) and it turns out that at -70 degrees C its surface is too warm to be just ice. It’s probably covered in a layer of darker dust — but that will likely change once the comet travels closer to the Sun and things really begin to “heat up!”

And, of course, Rosetta and Philae will be along for the ride, watching it all play out.

“With only a few days until we arrive at just 100 km distance from the comet, we are excited to start analysing this fascinating little world in more and more detail,” said VIRTIS principal investigator Fabrizio Capaccioni.

The 1066 appearance of Halley's Comet is represented in the Bayeaux Tapestry. "They Marveled at the Star" — *The 1066 appearance of Halley’s Comet is represented in the Bayeaux Tapestry. “They Marveled at the Star”*

Rosetta is truly the culmination of not just ten years of travel through the solar system, or even decades of comet research, but literally hundreds — perhaps even thousands — of years of fascination about these “long-haired” cosmic visitors. (“Comet” is from the Greek word for long-haired star!) Once thought to portend difficulty and doom for human endeavors, comets are now known to be visitors from the farthest reaches of our solar system, carrying materials that were present before the planets first formed. Learn more about the history of comets and their exploration along with Rosetta and Philae in this cartoon from ESA:

And if you want to learn more about the Rosetta mission and how it will achieve its objectives, check out this video from DLR (the German Aerospace Center) here: