In situ images of 67P/Churyumov-Gerasimenko acquired by the 7 CIVA cameras on board Philae revealed a singular, unexpected, and very irregular landscape dominated by consolidated materials. Following a detailed study, this landing site provided a unique opportunity to constrain the past and present conditions prevailing at the surface of the comet.
Gullies observed on Mars would be produced by the action of dry ice in winter and spring, not by liquid water flows as thought before. Indeed, recent numerical simulations show that under dry ice heated by the Sun, intense gas motions can destabilize and fluidize the soil, until they create flows similar to those created by a liquid.
Ongoing flow activity was highlighted a few years ago on Mars by high-resolution cameras. Various flow types have been identified (new channels, dark lineae, bright deposits…) but there is still no consensus about possible formation mechanisms: dry avalanche? liquid water? carbon dioxide ice? A study conducted at the Institut d’Astrophysique Spatiale reveals for the first time the composition of winter ice forming in association with flows. Results suggest the coexistence of several current formation mechanisms.
After 7 long months, Philae has awoken from hibernation. Its first signs of life reached Earth on Saturday evening (June, 13th) then again the following night. The hope to see Philae awake again and communicating has just come true.
The flight model of the SIMBIO-SYS instrument of the ESA BEPI-COLOMBO mission has arrived at IAS last week! IAS, who has already provided the main electronics of SIMBIO-SYS, is also in charge of the calibration of the integrated instrument that will take place during this month. The mission will be launched in 2017, for an arrival at Mercury in 2024.