technology:sublimation

#Rosetta catches dusty organics
▻http://blogs.esa.int/rosetta/2016/09/07/rosetta-catches-dusty-organics

Rosetta’s #dust-analysing COSIMA (COmetary Secondary Ion Mass Analyser) instrument has made the first unambiguous detection of solid organic matter in the dust particles ejected by #Comet_67P/Churyumov-Gerasimenko, in the form of complex carbon-bearing molecules. While organics had already been detected in situ on the comet’s surface by instruments on-board Philae and from orbit by #rosetta’s ROSINA , those were both in the form of gases resulting from the sublimation of ices. By contrast, COSIMA has made its detections in solid dust. Their presence was only ever hinted at in previous comet missions, which flew by their targets at high speed and, as a result, disrupted the particles, making characterisation challenging. But Rosetta is orbiting Comet 67P/C-G and can catch dust particles (...)

#Comets #Science #science

Krypton and xenon added to #Rosetta’s noble gas inventory
▻http://blogs.esa.int/rosetta/2016/06/14/krypton-and-xenon-added-to-rosettas-noble-gas-inventory

Rosetta has detected the noble gases krypton and xenon while flying close to #Comet_67P/Churyumov-Gerasimenko last month. The detections were made during dedicated orbits between 10 and 31 May, which took the spacecraft to within 10 km of the #comet’s surface, and sometimes as close as 5 km. The discovery was highlighted today by Kathrin Altwegg, Principal Investigator of the ROSINA instrument that made the detections, during a Royal Society meeting on ‘Cometary #Science after #rosetta ’ in London, UK. “We had sporadic hints of krypton while briefly flying at 12 km in early March, but the confirmation was only possible thanks to a longer period of observation during these close orbits,” she says. “Noble gases bound up inside the comet very easily escape into space through sublimation, so (...)

#Comets #Instruments #instruments #science

#comet #surface changes before #Rosetta’s eyes
▻http://blogs.esa.int/rosetta/2015/09/18/comet-surface-changes-before-rosettas-eyes

In the months leading to the #perihelion of #Comet_67P/Churyumov-Gerasimenko, #rosetta scientists have been witnessing dramatic and rapid surface changes on the #Imhotep region, as reported in a paper to be published in Astronomy & Astrophysics Since arriving at Comet 67P/C-G in August 2014, Rosetta has been witnessing an increase in the #activity of the comet, warmed by the ever-closer Sun. A general increase in the outflow of gas and dust has been punctuated by the emergence of jets and dramatic rapid outbursts in the weeks around perihelion, the closest point to the Sun on the comet’s orbit, which occurred on 13 August 2015. But in June 2015, just two months before perihelion, Rosetta scientists started noticing important changes on the surface of the nucleus itself. These very (...)

#Images #Instruments #Science #osiris #science #water

Seasonal forecasts for 67P/C-G
▻http://blogs.esa.int/rosetta/2015/02/09/seasonal-forecasts-for-67pc-g

Based on the press release of the Max Planck Institute for Solar System Research, Germany. Scientists from #Rosetta’s OSIRIS team have been analysing the images of #Comet_67P/Churyumov-Gerasimenko and comparing them to a thermal model to estimate how much material the various parts of the #comet will lose through Sun-driven sublimation during one orbit. That is, as the Sun heats the comet, ices sublimate and the resulting gases drag dust into the comet’s coma. The results predict that the southern half of the comet will undergo dramatic changes in the coming months, losing a surface layer several metres thick, while the northern half will likely be much less affected by the Sun-driven erosion. Followers of this blog might be familiar with the geography of Comet 67P/C-G, but it’s worth (...)

#Science #rosetta #science