At 5:29 a.m. EDT (9:29 a.m. GMT) on Aug. 6, 2014, the European Space Agency's comet-chasing spacecraft Rosetta was a comet-chaser no more. After 10 years and 3.7 billion miles, Rosetta reached its target, Comet 67P/Churyumov-Gerasimenko, to begin an unprecedented mission in cometary orbit -- the first mission to ever do so. Rosetta will remain in orbit as the comet swings past close approach of the sun, observing changes in the icy body's structure as they travel with one another.
Comets possess some of the most pristine material in the solar system, having been in deep freeze since before the formation of the planets. So through Rosetta's instruments we'll not only be studying a fascinating celestial body, we'll be probing billions of years into the past. To help achieve this goal, in November Rosetta will even drop a small probe, called Philae, to attempt the first ever landing on a comet's surface.
But for now, ESA has released the most detailed, and stunning, photos of 67P/Churyumov-Gerasimenko to date as Rosetta settles into orbit around the 2.5 mile-wide 'dirty snowball.'
Shown in this image is 67P/Churyumov-Gerasimenko in its entirety taken by Rosetta's OSIRIS narrow-angle camera on Aug. 3 from a distance of 177 miles.
The comet is composed to two very distinct "lobes" -- a configuration that made the cometary nucleus look like a "rubber ducky" during Rosetta's approach to 67P/Churyumov-Gerasimenko. Astronomers believe that the object may be a "contract binary," where two separate objects collided and fused together as one.
Shown here is an extreme closeup of a smooth region of the "body" (or the larger lobe) of the comet. The photo was captured on the day of rendezvous (Aug. 6) by Rosetta’s OSIRIS narrow-angle camera and it shows small boulders, cliffs and other, as-yet to be explained features. The resolution of this observation is 2.4 meters per pixel. Rosetta was a mere 81 miles from the comet.
Looking down on the comet's "body" from a distance of 177 miles on Aug. 3, 2014. Beautiful layering of material can be seen with big boulders breaking up large expanses of smooth terrain. This is a truly alien landscape and Rosetta has only just begun its mission to try to understand 67P/Churyumov-Gerasimenko's composition and dynamics.
Where the two lobes of 67P/Churyumov-Gerasimenko's mass meet, is a clearly defined "neck." As Rosetta was approaching the comet, a bright feature at the neck became clear, something that the mission will study to help us understand its nature. This photo was taken on Aug. 6, 2014, when the spacecraft was just 75 miles from the comet's surface, acquiring a resolution of 2.2 meters per pixel.
This earlier observation taken by the Rosetta probe as it was chasing the comet on Aug. 2, 2014, shows how active its nucleus is. The rays of light emanating from the top are jets of vapor forming the comet's coma, within which Rosetta is now orbiting. This cometary activity will increase as Comet 67P/Churyumov-Gerasimenko continues to approach the sun. And thanks to Rosetta, for the first time ever, we are going to have a ringside seat for the voyage.