De la Terre à Neptune : le grand voyage

L’observation des planètes est à l’origine de l’astronomie. Elle a connu un véritable essor au XVIIe siècle, avec l’apparition des premiers instruments et des grands observatoires. Puis, avec l’apparition de la spectroscopie, l’exploration des étoiles et des galaxies s’est développée à son tour, notamment dans la première moitié du XXe siècle, et l’intérêt des astronomes pour les planètes est passé momentanément au second plan.The observation of planets goes back to Antiquity. It strongly developed in the 17th century with the emergence of the first refractors and telescopes. Since the 1950s, the study of solar-system objects has known a new revolution, with the development of space planetary exploration. A new image of the solar system has emerged, with the in situ observations of planets and comets, and the discovery of a new class of objects beyond Neptune’s orbit. The French scientific community has played a significant role in this adventure, thanks in particular to its organization within CNRS and CNES

Enhanced acetylene emission near the north pole of jupiter

We report observations of acetylene emission lines near 13.3 [mu]m on Jupiter recorded at the NASA Infrared Telescope Facility in July 1984. A strong enhancement in the intensity of R10 line of the [nu]5 band was recorded within a well-localized region coincident with the southern extension of footprint of the Io magnetic lines and with previous observations of localized enhanced emission of CH4 lines. The line intensity was fairly constant outside this "bright spot." Moreover, weak lines of the hot bands 2[nu]5 - [nu]5, and ([nu]4 + [nu]5) - [nu]5 were observed within the bright spot. From the field of view and the precision of the pointing, the zone of activity of the bright spot is found to be: latitude = 59 +/- 10[deg] and longitude = 178 +/- 10[deg] (System III, 1965). The location of the spot was found to be constant over a 3-day period. Two interpretations are proposed to explain these observations: (1) a variation of the C2H2 abundance and (2) an alteration of the thermal profile in the bright spot. Either may result from precipitation of charged particles near and below the Jovian homopause.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/26158/1/0000235.pd

The atmospheres of extrasolar planets

The discovery of extrasolar planets, or “exoplanets” – i.e., planets orbiting around other stars – may be seen as the major discovery of astronomy over the past two decades. About twenty years ago, in 1992, the first discovery of a couple of planets around a pulsar was announced by A. Wolszczan and D. Frail

Current Results of Ground-based Planetary Spectroscopy

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From solar-system planets to exoplanets

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Jupiter la geante.

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An Overview of Mars Atmospheric Science Results with Mars Express

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Jupiter and the other Giants: A Comparative Study

International audienceThe four giant planets - Jupiter, Saturn, Uranus and Neptune - have common properties which make them very different from the terrestrial planets: located at large distances from the Sun, they have big sizes and masses but low densities; they all have a ring system and a large number of satellites. These common properties can be understood in the light of their formation scenario, based upon the accretion of protosolar gas on an initial icy core. Giant planets have been explored by space missions (Pioneer 10 and 11, Voyager 1 and 2, Galileo and Cassini) but also by Earth-orbiting satellites and ground-based telescopes. There are still open questions related to the origin and evolution of the giant planets, in particular their moderate migration, the origin of the cold planetesimals which formed Jupiter, the origin of the atmospheric dynamics in Jupiter and Saturn, and the differences in the internal structures of Uranus and Neptune

In memoriam Vasily Ivanovitch Moroz (1931 2004)

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