4 research outputs found
Color-differential astrometry with the NGST. Application to the spectroscopy of giant extrasolar planets
International audienceThe color-differential astrometry method consists in measuring the variations of the photocenter position with wavelength. This yields spectral information on the spatial structure of an unresolved source, and could allow, among other applications, the direct detection and spectroscopy of extrasolar planets. We give some estimates of signal-to-noise ratio for CDA using the the NGST mid-infrared instrument (MIRI) spectrograph, assuming for the planetary luminosity either black-body models or recent synthetic spectra. Giant Planets around nearby Sun-like stars are potentially observable over a wide-range of orbital distances, if the precision on the measurement is limited by th
Optical design for the 5-28mum NGST infrared imager MIRI
International audienc