PICARD
is an investigation dedicated to the Sun-climate connection. The mission
objectives are the study of the physics of the Sun and the solar forcing on the
Earth's climate by modeling. The following
measurements from space are: the absolute total and spectral solar irradiance,
the diameter and solar limb shape, and solar oscillations to probe the Sun's
interior. These measurements obtained all along the mission will allow us to
study their variations as a function of the solar activity. As ground-based
diameter measurements do not reveal consistent results, a correlative program
of ground-based observations will allow us to understand these variations by
comparing simultaneous solar diameter measurements from space and from ground.
We shall present the design of the instruments and their performances. The
today state of development of the mission and instruments will be shown. In parallel to the space instrumentation
development, a climate model including the stratosphere and a solar model are
undertaken.
The observations will be carried out
by three instruments placed on board a microsatellite
built by Centre National d'Etudes Spatiales
(France). The orbit will be
sun-synchronous and the launch is foreseen in early 2008.