Paper of the month
Nitrogen Atmospheres of the Icy Bodies in the Solar System
Manuel Scherf (Space Research Institute, Austrian Academy of Sciences) et al. 2020
This brief review will discuss the current knowledge on the origin and evolution of the nitrogen atmospheres of the icy bodies in the solar system, particularly of Titan, Triton and Pluto. An important tool to analyse and understand the origin and evolution of these atmospheres can be found in the different isotopic signatures of their atmospheric constituents.
N ratio of the N2
-dominated atmospheres of these bodies serve as a footprint of the building blocks from which Titan, Triton and Pluto originated and of the diverse fractionation processes that shaped these atmospheres over their entire evolution.
Together with other measured isotopic and elemental ratios such as 12
C or 36
these atmospheres can give important insights into the history of the icy bodies in the solar system, the diverse processes that affect their N2
-dominated atmospheres, and the therewith connected solar activity evolution.
Plasma distribution around Comet 67P in the last month of the Rosetta mission
Zoltán Németh (Wigner Research Centre for Physics, Budapest, Hungary) et al. 2020
After accompanying comet 67P/Churyumov–Gerasimenko on its journey around the Sun and observing the evolution of its induced magnetosphere throughout the comet’s life-cycle, the Rosetta operations concluded at the end of September 2016 with a controlled impact on the cometary nucleus. At that time, the comet was located more than 3.7 AU from the Sun, but the data still show clear indications of a weak but well developed plasma environment around the nucleus. Rosetta observed this fading cometary magnetosphere along multiple recurring elliptical orbits, which allow us to investigate its properties and spatial structure. We examined the measured electron and neutral densities along these consecutive orbits, from which we were able to determine the structure of the spatial plasma distribution using a simple latitude and longitude dependent model.