BRITE-Constellation

BRITE-Constellation, a project developed since 2003 by researchersxE2x88x97 at Canadian and Austrian Universities presently consists of UniBRITE and BRITE-Austria/TUG-SAT1, which are two 20 cm cube nanosatellites. Each will fly a 30 mm aperture telescope with a CCD camera equipped with either a red (550 to 700 nm) or a blue (390 to 460 nm) filter, to perform high-precision two-color photometry of the brightest stars in the sky ( ≤ 4th mag) for up to several years. Stars of up to two magnitudes fainter will be observed simultaneously with reduced accuracy in an on-board photometric mode. Depending on the orbit and the position of the BRITE targets the photometry can be obtained contiguously during many orbits for many months, with gaps during individual orbits, or only for certain periods of the year. The primary science goals are studies of massive and luminous stars in our neighbourhood, representing objects which dominate the ecology of our Universe, and of evolved stars (giants) to probe the future development of our Sun. The wide field cameras (24◦ ) will also obtain data from other scientifically interesting stars to investigate their stellar structure and evolution. All of this is enabled by innovative technology currently developed in collaboration between Canada and Austria. A launch of UniBRITE and BRITE-Austria in 2009 is envisioned and an expansion proposal of the BRITE-Constellation by two dditional spacecrafts of the same construction, to be funded by the Canadian Space Agency (CSA), is currently under review. A comprehensive description of scientific and technical aspects of BRITE-Constellation is being prepared for publication in Communications in Asteroseismology. The BRITE- Constellation web site can be found at www.brite-constellation.at. A first Announcement of Opportunity for submitting BRITE-Constellation observing proposals was issued at http://ams.astro.univie.ac.at/BRITE AO/BRITE AO.html