Search

Using infrared wavelengths, micrometre-sized water-ice grains have been identified on the nucleus (which is mostly coated in a dark material) of comet 67P/Churyumov–Gerasimenko.

Observations of water ice on the surface of comet 67P/Churyumov–Gerasimenko show the ice appearing and disappearing in a cyclic pattern that follows local illumination conditions, providing a source of localized activity and leading to cycling modification of the ice abundance on the surface.

The surface of Hyperion has a large region of high albedo with the signature of H₂O ice and another zone of albedo about a factor of four lower. Observations of the surface in the ultraviolet and near-infrared spectral regions with two optical remote sensing instruments on the Cassini spacecraft detail that the low-albedo material has spectral similarities and compositional signatures that link it with the surface of Phoebe.

Diurnal and seasonal temperature variations of comet 67P’s nucleus are monitored by Rosetta’s imaging spectrometer VIRTIS during two months in 2014. The nucleus appears thermally homogeneous, with the temperature fluctuations mainly controlled by self-heating and heliocentric distance.

A refined analysis of infrared observations of comet 67P/Churyumov–Gerasimenko from the VIRTIS instrument on board the Rosetta spacecraft has revealed the presence of aliphatic organic molecules on the comet nucleus.

Visible and infrared images obtained from above each pole of Jupiter by the Juno spacecraft reveal polygonal patterns of large cyclones; it is unknown how these cyclones evolved, or how they persist without merging.

Observations of infrared emission from CO₂, O₂ and NO established that photochemical and dynamic activity controls the structure of the upper atmosphere of Venus, but were unable to identify the altitude of the emission. But it is reported here that day-side CO₂ emission extends from 90–120 km altitude, with a peak at ∼115 km. Night-side O₂ emission peaks at 96 km and is visible over the range 95–100 km.

Venus has a bright 'dipole' double-eye feature at the centre of a vast vortex that rotates around the north pole, and is surrounded by a cold 'collar'. Observations of Venus' south polar region are reported, where clouds with morphology much like those around the north pole are seen, but rotating somewhat faster.