After over 12 years Rosetta will be decommissioned by sending it down to impact with comet 67P/C-G. This fate was decided as the comet is moving away from the sun, beyond the orbit of Jupiter and the solar panels will not generate enough power to keep the spacecraft operational. Even “hibernation” is not a possibility as heaters are still required to keep the critical systems idling. Hence mission control will send commands in the next few days such that on September 29th a series of maneuvers will send it on a impact trajectory with the comet. As the comet’s gravity is rather weak (1/10,000 of Earth’s) it will most likely not be a fatal impact. However the Rosetta will be instructed to shutdown upon contact with the surface in order not to “pollute” the deep space communication network with spurious and uncommanded signals. This is expected to happen on September 30th 10:40 GMT.
So where is comet 67P/C-G? Travelling towards the orbit of Jupiter, in constellation Virgo, opposite to the sun from Earth’s perspective. Normally an event like this would be timed to be observable at night from Earth such that telescopes can gather scientific data. But at apparent magnitude 20 (to compare, Pluto has a mean apparent magnitude of 15) it will be very difficult to observe. And the impact is not expected to generate a large plume of dust. Therefore it will be up to Rosetta to record and beam back to Earth as much data during the descent before shutting down for good.