Rosetta spacecraft spotted five round depressions in June, early July
MPS for OSIRIS Team/Rosetta/ESA, MPS/UPD/LAM/IAA/SSO/INTA/UPM/DASP/IDA
A comet is growing its own version of crop circles. Over the course of a month, five expanding disklike depressions appeared on the surface of 67P/Churyumov-Gerasimenko in images taken by the Rosetta spacecraft, which has been orbiting 67P since August 2014 (SN: 9/6/14, p. 8).
The first roundish feature showed up on June 3 and was joined by a second 10 days later. Within a month, the first spot had grown to 220 meters across and 5 meters deep, and it had run into its neighbor. Three more spots appeared in early July, flanking the original two, researchers report online September 15 in Astronomy & Astrophysics.
The spots form around weak points in the surface, where