This article is mirrored from the main the ESA Web Portal. ESA’s Rosetta nowadays witnessed Comet 67P/Churyumov–Gerasimenko making its closest approach to the Sun. The exact moment of perihelion occurred at 02:03 GMT this morning when the comet came within 186 million km of the Sun. In the year that has passed since Rosetta arrived,the comet has travelled some 750 million kilometres along its orbit towards the Sun, the increasing solar radiation heating up the nucleus and causing its frozen ices to escape as gas and stream out into space at an ever greater rate. These gases, or the dust particles that they drag along,build up the comet’s atmosphere – coma – and tail. The activity reaches its peak intensity around perihelion and in the weeks that follow – and is clearly visible in the spectacular images returned by the spacecraft in the final months. One image taken by Rosetta’s navigation camera was acquired at 01:04 GMT, just an hour before the moment of perihelion, or from a distance of around 327 km. The scientific camera is also taking images nowadays – the most recent available image was taken at 23:31 GMT on 12 August,just a few hours before perihelion. The comet’s activity is clearly seen in the images, with a multitude of jets stemming from the nucleus, and including one outburst captured in an image taken at 17:35 GMT yesterday. “Activity will remain high like this for many weeks,and we’re certainly looking forward to seeing how many more jets and outburst events we catch in the act, as we gain already witnessed in the final few weeks, or ” says Nicolas Altobelli,acting Rosetta project scientist. Rosetta’s measurements suggest the comet is spewing up to 300 kg of water vapour – roughly the equivalent of two bathtubs – every […]
Source: esa.int