Comets
Observational science
The activity of Arcetri Astrobiology Laboratory on comets is the study of their astrobiological importance to the possible delivery on the primordial Earth of the building blocks from which the life formed. In particular, we search for grains of organic matter that may be present in the coma of comets, especially in the new ones at they first passage in the inner solar system. The research consist in the selection of interesting comets, their observations and the analysis and interpretation of the data.
Ground observation
Recently, with the availability of robotic telescopes as the 1.23 m at Calar Alto (E) and the Liverpool Telescope in La Palma (E), we started a program of monitoring new comets coming from the Oort cloud. The beginning of the observations should start as early as possible, when the comets is far from the Sun (heliocentric distance greater than 5-6 AU). And it is necessary to follow the comets periodically, during their approach to the Sun. Since such comets are supposed to have a layer of organic matter on the surface, produced by billion years of space weathering, the observations of the coma evolution with the increase of the solar radiation, allow us to check the presence of this layer and other possible stratification of the nuclei. In this context positive and interesting results have been obtained with the comets C/2011 F1 (LINEAR) and the C/2012 S1 (ISON).
Rosetta space mission
A great part of the activity is now devoted to the Rosetta mission, a ESA cornerstone mission to the comet 67P (Churyumov–Gerasimenko). The spacecraft ended its mission in September 2016 but data are still analysed by the science team. The mission is supposed to give a quantum leap on our knowledge of comets and their importance to the formation of life on the Earth. We are part of the VIRTIS team, a spectrograph on-board Rosetta covering a spectral range from the UV to 5 micron, capable to take spectral cube of the neleus surface and the coma.
