ESA

Picture of the comet 67P/Churyumov-Gerasimenko near the perihelion (Photo ESA/Rosetta/NAVCAM)

During the day yesterday the comet 67P/Churyumov-Gerasimenko passed the perihelion, the point of closest approach to the Sun. ESA’s Rosetta space probe was at a distance of about 327 kilometers (about 203 miles) and with its NAVCAM instrument took a series of pictures to document the comet’s activities. Thanks to the heat it’s been receiving from the Sun the spectacular jets of gas generated by ice sublimation will continue for a few weeks.

Photo of the surface of the area of the comet 67P/Churyumov-Gerasimenko known as Agilkia taken by the Philae lander from a 9 m height (Photo ESA/Rosetta/Philae/ROLIS/DLR)

A special issue of the journal “Science” describes an early analysis of data collected by the lander Philae in its descent to the surface of the comet 67P/Churyumov-Gerasimenko. Its mission was short and ESA engineers can’t get a stable contact after those of recent weeks but the data collected were very helpful. Another very interesting study just appeared about the interaction of the comet with the solar wind.

One of the pits in the area called Seth on the surface of the comet 67P/Churyumov-Gerasimenko (Image ESA/Rosetta/MPS for OSIRIS Team MPS/UPD/LAM/IAA/SSO/INTA/UPM/DASP/IDA)

An article published in the journal “Nature” describes a research on a series of 18 pits on the comet 67P/Churyumov-Gerasimenko. They are nearly circular and some of them are a source of activity, emitting jets of gas and dust. They were discovered a long time ago but an analysis of the images collected by ESA’s space probe Rosetta’s OSIRIS camera allowed to establish that probably they were formed following a collapse of the surface.

Six of the icy areas on the surface of the comet 67P/Churyumov-Gerasimenko found by the Rosetta space probe (Image ESA/Rosetta/MPS for OSIRIS Team MPS/UPD/LAM/IAA/SSO/INTA/UPM/DASP/IDA)

The OSIRIS (Optical, Spectroscopic, and Infrared Remote Imaging System) camera on ESA’s space probe Rosetta allowed to identify 120 icy areas on the surface of the comet 67P/Churyumov-Gerasimenko. A study of the presence of ice has just been published in the journal “Astronomy & Astrophysics”. That presence was well known but Rosetta’s observations allowed to understand the phases of transformation into gas, how much of it forms the comet’s coma and tail and what falls back to the surface.