COBS News archive

CometWatch 12 November – one year on
November 14, 2015
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.

CometWatch from Gaia
November 05, 2015
On 14 September 2015, Comet 67P/Churyumov Gerasimenko was imaged by Gaia, ESA's billion star surveyor.

First detection of molecular oxygen at a comet
October 31, 2015
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 26 October – 6 hours apart
October 31, 2015
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.

CometWatch 18 October
October 31, 2015
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.

CometWatch 9 October
October 20, 2015
This image of Comet 67P/Churyumov-Gerasimenko was taken by Rosetta’s NAVCAM on 9 October from a distance of 579 km.

Comet jet in 3D
October 13, 2015
OSIRIS scientists have created a spectacular anaglyph view of a jet seen blasting from the nucleus of Comet 67P/Churyumov-Gerasimenko in August.

Interpreting images – more on how the comet got its shape
October 13, 2015
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.

CometWatch 1 October
October 09, 2015
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.

Comet Feature Named After Late NASA Scientist Claudia Alexander
October 04, 2015
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.

CometWatch 30 September – Far, far away
October 04, 2015
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.

Rosetta’s mass spectrometer ROSINA detected argon at comet Churyumov-Gerasimenko
October 03, 2015
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.

Rosetta’s first peek at the comet’s south pole
October 02, 2015
Using the Microwave Instrument for the Rosetta Orbiter (MIRO), scientists have studied the comets southern polar regions at the end of their long winter season. The data suggest that these dark, cold regions host ice within the first few tens of centimetres below the surface in much larger amounts than elsewhere on the comet.

An update on Comet 67P/C-G’s water-ice cycle
October 01, 2015
Last week we reported on the daily water-ice cycle of Comet 67P/Churyumov-Gerasimenko that was observed in a specific region of the comet’s neck by Rosetta’s VIRTIS instrument, in September 2014.

Cometwatch 21 September
September 28, 2015
Today's CometWatch entry was taken by Rosetta’s NAVCAM on 21 September 2015, about 330 km from the nucleus of Comet 67P/Churyumov-Gerasimenko.

Comet surface changes before Rosetta’s eyes
September 28, 2015
Since arriving at Comet 67P/C-G in August 2014, Rosetta has been witnessing an increase in the activity of the comet, warmed by the ever-closer Sun. A general increase in the outflow of gas and dust has been punctuated by the emergence of jets and dramatic rapid outbursts in the weeks around perihelion, the closest point to the Sun on the comet’s orbit, which occurred on 13 August 2015.

CometWatch 11 September
September 25, 2015
Today's CometWatch entry was taken by Rosetta’s NAVCAM on 11 September 2015, about 319 km from the nucleus of Comet 67P/Churyumov-Gerasimenko.

New Comet: P/2015 Q2 (PIMENTEL)
September 25, 2015
CBET nr. 4140, issued on 2015, September 02, announces the discovery of a comet (magnitude ~18.5) by Eduardo Pimentel on Aug. 24.2 UT with a 0.45-m f/2.9 reflector of the SONEAR Observatory at Oliveira. Follow-up observations to confirm the object were obtained by C. Jacques, E. Pimentel, and J. Barros with the same telescope on Aug. 27.3 and31.3. The new comet has been designated P/2015 Q2 (PIMENTEL).

CometWatch 5 September
September 15, 2015
Today's CometWatch entry was taken by Rosetta’s NAVCAM on 5 September 2015, about 445 km from the nucleus.

CometWatch 30 August
September 15, 2015
Today's CometWatch entry was taken by Rosetta’s NAVCAM on 30 August 2015, about 404 km from the nucleus.