The Darwin mission: Search for extra-solar planets

The direct detection of an Earth-like planet close to its parent star is challenging because the signal detected from the parent star is between 10(9) and 10(6) times brighter than the signal of a planet in the visual and IR respectively. Future space based missions like Darwin and TPF-I concentrate on the mid-IR region between 6 and 20 mu m, a region that contains the CO2, H2O, O-3 spectral features of biomarkers in Earth's atmosphere. The InfraRed Space Interferometer Darwin is an integral part of ESAs Cosmic Vision 2020 plan, intended for a launch towards the middle of the next decade. It has been the subject of a feasibility study and is now undergoing technological development. It is focused on the search for, and characterization of Earth-like planets orbiting other stars. A secondary objective is to carry out imaging of astrophysical objects with unprecedented spatial resolution. The implementation is based on the new technique of 'nulling interferometry'. New designs have been developed that will be implemented on four spacecrafts and search for planets around a minimum of 165 stars within the mission lifetime. (c) 2005 COSPAR. Published by Elsevier Ltd. All rights reserved.