Free Astronomy Magazine September-October 2014

SMALL BODIES around 100 km, ESA engineers expect to be able to bring the probe to about 30 km from the surface, but much will depend on the level of activity that the comet will reach on its way to the appointment with the perihelion on 13 Au- gust 2015, and thus on how the coma will develop. The pressure produced by the latter, however moderate, will inevitably disturb the orbital motion of Rosetta, but even more directly it will pose a danger to the small Philae, which is equip- ped with an anchoring system for securing it to its surface as soon as it lands on it next November. Either the day and exact location of the landing have yet to be confirmed, since Ro- I mages taken on 11, 12 and 13 August (top, mid- dle and bottom, respectively), just a little over 100 km from the comet. [ESA/Ro- setta/NAVCAM] from 67P/Churyumov-Gerasimenko, OSIRIS started to reveal with good resolution images its surface corrugations, but it is on 3 August that at a distance of just 285 km the rough exterior of the nucleus showed up in high resolution, with the smallest details about 5 metres wide. Three days later there was the historic rendezvous, with Rosetta beginning the series of final manoeuvres that by Octo- ber will take it to orbit stably (even if with some fluctuations) around the comet. Al- though the orbital altitude will initially be