Rosetta Details

Rosetta/Philae's primary mission ended in the morning of 15.11.2014, 03:15 Finnish time

After the depletion of the primary battery and the recharged secondary battery the contact between Rosetta and Philae stopped and re-started a few times until it failed completely. Last information showed the empty battery status. Philae's control system as final activity changed into Long Term Science mode and activated its low-power stand by mode where it will remain until sufficient solar power is available for a restart.

Separation and Landing:

Separation happened as planned on 12.11. at 10:35 Finnish time. After 2 hours of flight without communication the radio link between Philae and Rosetta was established 13:00. All operations during the descent were performed as planned, all systems were nominally,

After precise point landing in the intended area neither down-hold thruster nor the harpoons activated successfully. The ice screws were not able to hold the lander which took off again for another 2 hours flight after which it settled in a niche of a cliff at the edge of area 'B'. Here it performed most of the intended initial measurements before shutting down when the batteries run out.

Problems: APXS doors did not open, so that only reference spectra were measured, the MUPUS-PEN was not able to penetrate into the very hard ice body and stands now only inside the dusty top layer. The measurement sequence itself went as planned. It is not clear how deep the drill entered the soil and if the taken sample contained much material for the subsequent analysis by COSAC.

Due to the shadowing on three sides the efficiency of the solar panels for accu recharging during only 1.6 hours sun light is not high. It was improved by a final rotation of the Lander body presenting the largest available panel towards the opening

Advantages: The "hopping" from the original to the final landing site allowed measurement of species from different locations which showed to be significantly different. The danger of getting fast a cover of the solar panels is much smaller than at the original landing site. Due to its protection it might be able to operate even close to the Sun and beyond perihelion without the danger of overheating which otherwise would have terminated the Philae mission latest in March 2015.

For additional information and Finnish contributions to Rosetta follow this link.