Search Publications
The global meter-level shape model of comet 67P/Churyumov-Gerasimenko
Jorda, L.; Lara, L. M.; Bertaux, J. -L. +42 more
We performed a stereo-photogrammetric (SPG) analysis of more than 1500 Rosetta/OSIRIS NAC images of comet 67P/Churyumov-Gerasimenko (67P). The images with pixel scales in the range 0.2-3.0 m/pixel were acquired between August 2014 and February 2016. We finally derived a global high-resolution 3D description of 67P's surface, the SPG SHAP7 shape mo…
Formation of bi-lobed shapes by sub-catastrophic collisions. A late origin of comet 67P's structure
Benz, W.; Jutzi, M.
Context. The origin of the particular shape of comet 67P/Churyumov-Gerasimenko (67P) is a topic of active research. How and when it acquired its peculiar characteristics has distinct implications on the origin of the solar system and its dynamics.
Aims: We investigate how shapes such as that of comet 67P can result from a new type of low-ener…
Cold and warm electrons at comet 67P/Churyumov-Gerasimenko
Wahlund, J. -E.; Nilsson, H.; André, M. +20 more
Context. Strong electron cooling on the neutral gas in cometary comae has been predicted for a long time, but actual measurements of low electron temperature are scarce.
Aims: Our aim is to demonstrate the existence of cold electrons in the inner coma of comet 67P/Churyumov-Gerasimenko and show filamentation of this plasma.
Methods: In s…
How primordial is the structure of comet 67P?. Combined collisional and dynamical models suggest a late formation
Benz, W.; Morbidelli, A.; Jutzi, M. +2 more
Context. There is an active debate about whether the properties of comets as observed today are primordial or, alternatively, if they are a result of collisional evolution or other processes.
Aims: We investigate the effects of collisions on a comet with a structure like 67P/Churyumov-Gerasimenko (67P). We develop scaling laws for the critica…
Seasonal erosion and restoration of the dust cover on comet 67P/Churyumov-Gerasimenko as observed by OSIRIS onboard Rosetta
Jorda, L.; Lamy, P. L.; Lara, L. M. +51 more
Context. Dust deposits or dust cover are a prevalent morphology in the northern hemi-nucleus of comet 67P/Churyumov-Gerasimenko (67P). The evolution of the dust deposits was captured by the OSIRIS camera system onboard the Rosetta spacecraft having escorted the comet for over two years. The observations shed light on the fundamental role of cometa…
Hybrid modelling of cometary plasma environments. I. Impact of photoionisation, charge exchange, and electron ionisation on bow shock and cometopause at 67P/Churyumov-Gerasimenko
Kallio, E.; Gunell, H.; Behar, E. +7 more
Context. The ESA/Rosetta mission made it possible to monitor the plasma environment of a comet, from near aphelion to perihelion conditions. To understand the complex dynamics and plasma structures found at the comet, a modelling effort must be carried out in parallel.
Aims: Firstly, we present a 3D hybrid model of the cometary plasma environ…
Spatially resolved evolution of the local H2O production rates of comet 67P/Churyumov-Gerasimenko from the MIRO instrument on Rosetta
Ip, W. -H.; Hartogh, P.; Lellouch, E. +11 more
Aims: Using spectroscopic and continuum data measured by the MIRO instrument on board Rosetta of comet 67P/Churyumov-Gerasimenko, it is possible to derive and track the change in the water production rate, to learn how the outgassing evolves with heliocentric distance. The MIRO data are well suited to investigate the evolution of 67P, in unpr…
Isotopic composition of CO2 in the coma of 67P/Churyumov-Gerasimenko measured with ROSINA/DFMS
Wurz, P.; Altwegg, K.; Balsiger, H. +15 more
Context. Measurements of isotopic abundances in cometary ices are key to understanding and reconstructing the history and origin of material in the solar system. Comets are considered the most pristine material in the solar system. Isotopic fractionation (enrichment of an isotope in a molecule compared to the initial abundance) is sensitive to env…
Is near-surface ice the driver of dust activity on 67P/Churyumov-Gerasimenko
Keller, H. U.; Hartogh, P.; Rezac, L. +1 more
Context. Mainly for historical reasons, nearly all of the current thermophysical models of dust activity rely on the poorly justified assumption of cohesionless dust lifted by a gas drag force against the weak nucleus gravity. The interpretation of Rosetta data and our understanding of comet activity is particularly sensitive to this assumption. <…
Cliffs versus plains: Can ROSINA/COPS and OSIRIS data of comet 67P/Churyumov-Gerasimenko in autumn 2014 constrain inhomogeneous outgassing?
Jorda, L.; Altwegg, K.; Sierks, H. +18 more
Context. This paper describes the modelling of gas and dust data acquired in the period August to October 2014 from the European Space Agency's Rosetta spacecraft when it was in close proximity to the nucleus of comet 67P/Churyumov-Gerasimenko.
Aims: With our 3D gas and dust comae models this work attempts to test the hypothesis that cliff ac…