Astronomers have responded to the buzz about a mysterious dimming star by studying data from NASA's Spitzer Space Telescope. They conclude the dimming was probably caused by a family of comets passing in front of the star.
This week’s Cometwatch entry was taken by Rosetta’s NAVCAM on 27 November 2015 when the spacecraft was 124 km from the nucleus of Comet 67P/Churyumov-Gerasimenko.
Today's CometWatch entry is a NAVCAM image taken on 17 November 2015, when Rosetta was 141.4 km from the nucleus of Comet 67P/Churyumov-Gerasimenko. The spacecraft has not been this close to the nucleus since weeks before perihelion, when the increased amounts of dust due to enhanced comet activity started interfering with navigation and Rosetta remained at larger distances from 67P/C-G.
As announced in June along with confirmation of the mission’s extension, Rosetta teams are planning to end the operational phase of the mission in a controlled impact of the orbiter on the surface of Comet 67P/Churyumov-Gerasimenko at the end of September 2016. While the specific details of the trajectories and impact site are still under discussion, ESA’s Rosetta Spacecraft Operations Manager Sylvain Lodiot, Project Scientist Matt Taylor, and mission manager Patrick Martin, share some background information on the planning of this dramatic mission finale.
CBET nr. 4161, issued on 2015, November 05, announces the discovery of a comet (magnitude ~17.1) by J. A. Johnson on CCD images obtained with the Catalina Sky Survey's 0.68-m Schmidt telescope on Nov. 3.5 UT. The new comet has been designated C/2015 V2 (JOHNSON).
Today’s CometWatch entry was taken yesterday by Rosetta’s NAVCAM, on the anniversary of Philae’s historic landing on Comet 67P/Churyumov-Gerasimenko last year. The image was taken from a distance of 177.7 km; the image scale is 15.1 m/pixel and the image measures 15.5 km across. It has been lightly enhanced to better show the comet’s activity.
On 14 September 2015, Comet 67P/Churyumov Gerasimenko was imaged by Gaia, ESA's billion star surveyor.
ESA’s Rosetta spacecraft has made the first in situ detection of oxygen molecules outgassing from a comet, a surprising observation that suggests they were incorporated into the comet during its formation. This news story is mirrored from the main ESA web portal.
CometWatch this week comprises two NAVCAM images acquired six hours apart on 26 October 2015. The images have been lightly enhanced to reveal some detail of the comet’s activity (the unprocessed images are available at the end of the post). In the six hours that passed Rosetta also moved 2.3 kilometres closer to the comet, resulting in slightly different image scales between the two images.