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.
Today's CometWatch entry was taken by Rosetta’s NAVCAM on 18 October 2015, at 433 km from the nucleus of Comet 67P/Churyumov-Gerasimenko.
This image of Comet 67P/Churyumov-Gerasimenko was taken by Rosetta’s NAVCAM on 9 October from a distance of 579 km.
OSIRIS scientists have created a spectacular anaglyph view of a jet seen blasting from the nucleus of Comet 67P/Churyumov-Gerasimenko in August.
On 28 September, a scientific paper was published in Nature, presenting a view on the formation scenario of Comet 67P/Churyumov-Gerasimenko, based on Rosetta OSIRIS images (read our news report here). The paper, led by Dr Matteo Massironi of the University of Padova, Italy, evaluated two possible models to explain the comet's curious shape: the merging of two cometesimals or the erosion of a single object. Observational data and thorough analysis of the comet's gravity field pointed towards the first of the two hypotheses: 67P/C-G seems to have originated from two separately formed comets that merged at low speed.
Today's CometWatch entry is an image from Rosetta’s NAVCAM taken on 1 October 2015, at a distance of 1323 km from the nucleus of Comet 67P/Churyumov-Gerasimenko.
Scientists from the European Space Agency's Rosetta mission are honoring their deceased colleague, Claudia Alexander of NASA's Jet Propulsion Laboratory in Pasadena, California, by naming a feature after her on the mission's target, comet 67P/Churyumov-Gerasimenko.
Today's CometWatch entry is an image taken by Rosetta’s NAVCAM on 30 September 2015, about 1488 km from the nucleus of Comet 67P/Churyumov-Gerasimenko. The image was taken a few hours after the spacecraft had reached the farthest point – 1500 km from the nucleus – on its far excursion to study the coma and plasma environment of 67P/C-G on a broader scale.
The mass spectrometer ROSINA on ESA’s comet probe Rosetta has for the first time detected the noble gas argon in the coma of 67P/Churyumov-Gerasimenko. This measurement adds to the debate about the role of comets in delivering various "ingredients," such as water, to Earth.