The Surface Distributions of the Production of the Major Volatile Species, HO, CO, CO and O, from the Nucleus of Comet 67P/Churyumov-Gerasimenko throughout the Rosetta Mission as Measured by the ROSINA Double Focusing Mass Spectrometer.

The Rosetta Orbiter Spectrometer for Ion and Neutral Analysis (ROSINA) suite of instruments operated throughout the over two years of the Rosetta mission operations in the vicinity of comet 67P/Churyumov-Gerasimenko. It measured gas densities and composition throughout the comet's atmosphere, or coma. Here we present two-years' worth of measurements of the relative densities of the four major volatile species in the coma of the comet, HO, CO, CO and O, by one of the ROSINA sub-systems called the Double Focusing Mass Spectrometer (DFMS).

Krypton isotopes and noble gas abundances in the coma of comet 67P/Churyumov-Gerasimenko.

The Rosetta Orbiter Spectrometer for Ion and Neutral Analysis mass spectrometer Double Focusing Mass Spectrometer on board the European Space Agency's Rosetta spacecraft detected the major isotopes of the noble gases argon, krypton, and xenon in the coma of comet 67P/Churyumov-Gerasimenko. Earlier, it was found that xenon exhibits an isotopic composition distinct from anywhere else in the solar system. However, argon isotopes, within error, were shown to be consistent with solar isotope abundances.

The impact of an ICME on the Jovian X-ray aurora.

We report the first Jupiter X-ray observations planned to coincide with an interplanetary coronal mass ejection (ICME). At the predicted ICME arrival time, we observed a factor of ∼8 enhancement in Jupiter's X-ray aurora. Within 1.

Prebiotic chemicals-amino acid and phosphorus-in the coma of comet 67P/Churyumov-Gerasimenko.

The importance of comets for the origin of life on Earth has been advocated for many decades. Amino acids are key ingredients in chemistry, leading to life as we know it. Many primitive meteorites contain amino acids, and it is generally believed that these are formed by aqueous alterations.

Detection of argon in the coma of comet 67P/Churyumov-Gerasimenko.

Comets have been considered to be representative of icy planetesimals that may have contributed a significant fraction of the volatile inventory of the terrestrial planets. For example, comets must have brought some water to Earth. However, the magnitude of their contribution is still debated.

Saturn's variable magnetosphere.

Since the Cassini spacecraft reached Saturn's orbit in 2004, its instruments have been sending back a wealth of data on the planet's magnetosphere (the region dominated by the magnetic field of the planet). In this Viewpoint, we discuss some of these results, which are reported in a collection of reports in this issue. The magnetosphere is shown to be highly variable and influenced by the planet's rotation, sources of plasma within the planetary system, and the solar wind.

An interplanetary shock traced by planetary auroral storms from the Sun to Saturn.

A relationship between solar activity and aurorae on Earth was postulated long before space probes directly detected plasma propagating outwards from the Sun. Violent solar eruption events trigger interplanetary shocks that compress Earth's magnetosphere, leading to increased energetic particle precipitation into the ionosphere and subsequent auroral storms. Monitoring shocks is now part of the 'Space Weather' forecast programme aimed at predicting solar-activity-related environmental hazards.