Search Publications
Prebiotic chemicals--amino acid and phosphorus--in the coma of comet 67P/Churyumov-Gerasimenko
Wurz, P.; Bochsler, P.; Altwegg, K. +29 more
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. In the collector aerogel and foil samples of the Stardus…
The global shape, density and rotation of Comet 67P/Churyumov-Gerasimenko from preperihelion Rosetta/OSIRIS observations
Jorda, L.; Lara, L. M.; Lamy, P. +45 more
The Rosetta spacecraft reached Comet 67P/Churyumov-Gerasimenko (hereafter 67P/C-G) in August 2014 at an heliocentric distance of 3.6 a.u. and was then put in orbit around its nucleus to perform detailed observations. Among the collected data are the images acquired by the OSIRIS instrument up to the perihelion passage of the comet in August 2015, …
A homogeneous nucleus for comet 67P/Churyumov-Gerasimenko from its gravity field
Jorda, L.; Pätzold, M.; Sierks, H. +13 more
Cometary nuclei consist mostly of dust and water ice. Previous observations have found nuclei to be low-density and highly porous bodies, but have only moderately constrained the range of allowed densities because of the measurement uncertainties. Here we report the precise mass, bulk density, porosity and internal structure of the nucleus of come…
Evolution of water production of 67P/Churyumov-Gerasimenko: An empirical model and a multi-instrument study
Altwegg, K.; Huang, Z.; Nilsson, H. +24 more
We examine the evolution of the water production of comet 67P/Churyumov-Gerasimenko during the Rosetta mission (2014 June-2016 May) based on in situ and remote sensing measurements made by Rosetta instruments, Earth-based telescopes and through the development of an empirical coma model. The derivation of the empirical model is described and the m…
Sulphur-bearing species in the coma of comet 67P/Churyumov-Gerasimenko
Altwegg, K.; Balsiger, H.; Berthelier, J. J. +15 more
Several sulphur-bearing species have already been observed in different families of comets. However, the knowledge on the minor sulphur species is still limited. The comet's sulphur inventory is closely linked to the pre-solar cloud and holds important clues to the degree of reprocessing of the material in the solar nebula and during comet accreti…
Evolution of the Dust Size Distribution of Comet 67P/Churyumov-Gerasimenko from 2.2 au to Perihelion
Jorda, L.; Lamy, P. L.; Bertaux, J. -L. +74 more
The Rosetta probe, orbiting Jupiter-family comet 67P/Churyumov-Gerasimenko, has been detecting individual dust particles of mass larger than 10-10 kg by means of the GIADA dust collector and the OSIRIS Wide Angle Camera and Narrow Angle Camera since 2014 August and will continue until 2016 September. Detections of single dust particles …
The primordial nucleus of comet 67P/Churyumov-Gerasimenko
Jorda, L.; Lamy, P. L.; Lara, L. M. +45 more
Context. We investigate the formation and evolution of comet nuclei and other trans-Neptunian objects (TNOs) in the solar nebula and primordial disk prior to the giant planet orbit instability foreseen by the Nice model.
Aims: Our goal is to determine whether most observed comet nuclei are primordial rubble-pile survivors that formed in the s…
Refractory and semi-volatile organics at the surface of comet 67P/Churyumov-Gerasimenko: Insights from the VIRTIS/Rosetta imaging spectrometer
Fornasier, S.; Erard, S.; Drossart, P. +34 more
The VIRTIS (Visible, Infrared and Thermal Imaging Spectrometer) instrument aboard the Rosetta spacecraft has performed extensive spectral mapping of the surface of comet 67P/Churyumov-Gerasimenko in the range 0.3-5 µm. The reflectance spectra collected across the surface display a low reflectance factor over the whole spectral range, two spe…
Aggregate dust particles at comet 67P/Churyumov-Gerasimenko
Jessberger, Elmar K.; Torkar, Klaus; Levasseur-Regourd, Anny-Chantal +9 more
Comets are thought to preserve almost pristine dust particles, thus providing a unique sample of the properties of the early solar nebula. The microscopic properties of this dust played a key part in particle aggregation during the formation of the Solar System. Cometary dust was previously considered to comprise irregular, fluffy agglomerates on …
Origins of volatile elements (H, C, N, noble gases) on Earth and Mars in light of recent results from the ROSETTA cometary mission
Mousis, Olivier; Morbidelli, Alessandro; Altwegg, Kathrin +6 more
Recent measurements of the volatile composition of the coma of Comet 67P/Churyumov-Gerasimenko (hereafter 67P) allow constraints to be set on the origin of volatile elements (water, carbon, nitrogen, noble gases) in inner planets' atmospheres. Analyses by the ROSINA mass spectrometry system onboard the Rosetta spacecraft indicate that 67P ice has …