September 29, 2015

On the left, OSIRIS images used to visually identify over 100 terraces (green). In the middle, a 3D shape model used to determine the directions in which the terraces/strata are sloping and to visualise how they extend into the subsurface. On the right, local gravity vectors visualised on the comet shape model perpendicular to the terrace/strata planes (Image ESA/Rosetta/MPS for OSIRIS Team MPS/UPD/LAM/IAA/SSO/INTA/UPM/DASP/IDA; M. Massironi et al (2015))

1

At the European Planetary Science Congress going on these days in Nantes, France, evidence were presented that the strange shape of the nucleus of comet 67P/Churyumov-Gerasimenko is due to the fact that it was born from the merger of two small comets occurred a few billion years ago. The study conducted by a team led by Matteo Massironi, a researcher at the University of Padua and Italian INAF (National Institute of Astrophysics) associate, was published in the journal “Nature”.

Image of narrow streaks of water on Martian slopes at Hale Crater (Image NASA/JPL-Caltech/Univ. of Arizona)

3

Yesterday NASA announced the existence of flows of liquid water on Mars. The study, just published in the journal “Nature Geoscience”, is based upon years of analysis of data collected mainly thanks to the NASA’s MRO (Mars Reconnaissance Orbiter) space probe. The images captured by its camera and spectrometric data allowed to find streams of water along the walls of craters and slopes that vary over time and perchlorate salts in them.