Giotto Spacecraft

International audienceThe Giotto spacecraft (Fig. 1), the first ESA (European Space Agency) interplanetary probe, was designed to flyby comet Halley. Launched on 2 July 1985 by an Ariane-1 rocket from Kourou, Giotto succeeded in approaching the cometary nucleus to within 600 km on 14 March 1986. Through its first accurate images of a nucleus and in situ studies of gases and dust particles within a coma, the mission has revealed the complexity of comets. Afterwards, the Giotto spacecraft was re-oriented in order to study comet Grigg-Skjellerup, which was flown by on 10 July 1992, at a nucleus distance in the 150–200 km range

High-molecular-weight organic matter in the particles of comet 67P/Churyumov–Gerasimenko

International audienceThe presence of solid carbonaceous matter in cometary dust was established by the detection of elements such as carbon, hydrogen, oxygen and nitrogen in particles from comet 1P/Halley1, 2. Such matter is generally thought to have originated in the interstellar medium3, but it might have formed in the solar nebula—the cloud of gas and dust that was left over after the Sun formed4. This solid carbonaceous material cannot be observed from Earth, so it has eluded unambiguous characterization5. Many gaseous organic molecules, however, have been observed6, 7, 8, 9; they come mostly from the sublimation of ices at the surface or in the subsurface of cometary nuclei8. These ices could have been formed from material inherited from the interstellar medium that suffered little processing in the solar nebula10. Here we report the in situ detection of solid organic matter in the dust particles emitted by comet 67P/Churyumov–Gerasimenko; the carbon in this organic material is bound in very large macromolecular compounds, analogous to the insoluble organic matter found in the carbonaceous chondrite meteorites11, 12. The organic matter in meteorites might have formed in the interstellar medium and/or the solar nebula, but was almost certainly modified in the meteorites’ parent bodies11. We conclude that the observed cometary carbonaceous solid matter could have the same origin as the meteoritic insoluble organic matter, but suffered less modification before and/or after being incorporated into the comet

Rapport de mission effectuee a Semicon-Europa 83, Zurich, du 7 au 10 mars 1983

SIGLECNRS-CDST / INIST-CNRS - Institut de l'Information Scientifique et TechniqueFRFranc