Tag Archives: Comet 67P/Churyumov–Gerasimenko

Contrasting Terrains on Comet Churyumov-Gerasimenko 


 Where should Philae land? As ESA’s robotic spacecraft Rosetta circles toward Comet 67P/ Churyumov-Gerasimenko, a decision must eventually be made as to where its mechanical lander should attempt to touch-down. Reaching the comet earlier this month, Rosetta is sending back detailed pictures of the comet’s unusual nucleus from which a smooth landing site will be selected. Pictured above, near the image top, the head of the comet’s nucleus shows rugged grooves, while near the image bottom, the body shows a patch-work of areas sometimes separated by jagged hills. Some of the patch-work areas apparent on both the head and bodyseem to have fields of relatively smooth terrain. In the connecting area called the neck, however, visible across the image center, a relatively large swath of light-colored smooth terrain appears, punctuated occasionally bylarge boulders. Rosetta is scheduled to release Philae toward the dark mountain-sized comet nucleus with an anticipated landing date in November.

APOD NASA 19-Aug-14

Rosetta Approaches Comet Churyumov-Gerasimenko 

Image Credit & Copyright: ESA, Rosetta spacecraft, NavCam imager; Music: Eine kleine Nachtmusik (Mozart)

What does it look like to approach a comet? Early this month humanity received a new rendition as the robotic Rosetta spacecraft went right up to — and began orbiting — the nucleus of Comet 67P/Churyumov-Gerasimenko. This approach turned out to be particularly fascinating because the comet nucleus first revealed itself to have an unexpected double structure, and later showed off an unusual and craggily surface. The above 101-frame time-lapse video details the approach of the spacecraft from August 1 through August 6. The icy comet’s core is the size of a mountain and rotates every 12.7 hours. Rosetta’s images and data may shed light on the origin of comets and the early history of our Solar System. Later this year, Rosetta is scheduled to release the Philae lander, which will attempt to land on Comet Churyumov–Gerasimenko’s periphery and harpoon itself to the surface.

APOD NASA 11-Aug-14

Rosetta’s Rendezvous 


 On August 3rd, the Rosetta spacecraft’s narrow angle camera captured this stunning image of the nucleus of Comet 67P/Churyumov-Gerasimenko. After 10 years and 6.5 billion kilometers of travel along gravity assist trajectories looping through interplanetary space, Rosetta had approached to within 285 kilometers of its target. The curious double-lobed shape of the nucleus is revealed in amazing detail at an image resolution of 5.3 meters per pixel. About 4 kilometers across, the comet nucleus is presently just over 400 million kilometers from Earth, between the orbits of Jupiter and Mars. Now the first spacecraft to achieve a delicate orbit around a comet, Rosetta will swing to within 50 kilometers and closer in the coming weeks, identifiying candidate sites for landing its probe Philae later this year.

APOD NASA 07-Aug-14

Spacecraft Rosetta Shows Comet has Two Components 


 Why does this comet’s nucleus have two components? The surprising discovery that Comet 67P/Churyumov–Gerasimenko has a double nucleus came late last week as ESA’s robotic interplanetary spacecraft Rosetta continued its approach toward the ancient comet’s core. Speculative ideas on how the double core was created include, currently, that Comet Churyumov–Gerasimenko is actually the result of the merger of two comets, that the comet is a loose pile of rubble pulled apart by tidal forces, that ice evaporation on the comet has been asymmetric, or that the comet has undergone some sort of explosive event. Pictured above, the comet’s unusual 5-km sized comet nucleus is seen rotating over the course of a few hours, with each frame taken 20-minutes apart. Better images — and hopefully more refined theories — are expected as Rosetta is on track to enter orbit around Comet Churyumov–Gerasimenko’s nucleus early next month, and by the end of the year, if possible, land a probe on it.

APOD NASA 21-Jul-2014