Observatoire de Paris, Meudon, France
The ISO observations of Solar System objects have been crown with considerable
success. The amount, quality and diversity of the results exceeds most
expectations. This success is due, in a large part, to the outstanding
performances of the SWS instrument, and to the close cooperation between the
SWS team and Solar System Mission Scientist T. Encrenaz and her team.
The lucky appearance of comet Hale-Bopp during the lifetime of the
mission was another factor. The results cover a variety of areas: (1)
the formation of Giant Planets (2) the physics and composition of planetary
atmospheres and environments (3) the composition and thermal properties
of planetary, satellite and asteroid surfaces (4) the composition of cometary
atmospheres, ices and dust and their implications for cometary activity
and formation (5) the composition and properties of interplanetary dust. This
talk will highlight the most important results known to the author at that
time. As an appetizer: ISO has allowed the first detection of
(i) the far-IR lines of HD in the four Giant Planets, allowing a coherent
determination of their D/H ratio (ii) water vapor in the upper atmosphere
of the four Giant Planets and Titan, implying the existence of an external
source of oxygen in these objects, probably linked to interplanetary dust
particles (iii) new hydrocarbon species of the Giant
Planets, notably
CH3, C6H6, C3H4 and C4H2 in Saturn, with implications
for the chemistry and vertical transport in their stratospheres (iv)
the spectral signature of NH3 clouds in Jupiter's atmosphere (v)
a low, undersaturated, abundance of water in Saturn's upper troposphere (vi)
the presence of crystalline silicates in a short-period comet (P/Hartley 2),
and of Mg-rich crystalline silicates (forsterite) in Oort-cloud comet
Hale-Bopp (vii) the abundant
presence of CO2 in these two comets. Other results non-exhaustively
include an indication for the long-sought presence
of carbonates on Mars, the first observation of a thermal lightcurve
for Pluto and the evidence for narrow features near 10 
m in the
spectrum of Vesta.