Six years of stellar astrophysics with BRITE Constellation

BRIght Target Explorer (BRITE) Constellation is an international nanosatellite space astronomy mission performing high-cadence, long-term, two-colour photometric monitoring of the brightest stars in the sky. The mission consists of six nanosatellites (hence “Constellation”): two from Austria, two from Canada, and two from Poland, launched in 2013 and 2014. Each 7 kg nanosat carries an optical telescope of aperture 3 cm feeding an uncooled CCD. One instrument in each pair is equipped with a blue filter, the other with a red filter. Each BRITE instrument has a wide field of view (~24 degrees) so up to about 30 stars can be observed simultaneously. The Constellation is supported by a network of three ground stations. The BRITE observational sample is dominated by the most intrinsically luminous stars: massive stars at all evolutionary stages, and lower-mass stars at the end of their nuclear burning phases. The goals of BRITE-Constellation are (1) to measure p- and g-mode pulsations to probe the interiors and ages of stars through asteroseismology; (2) to detect stellar surface and wind structures, and measure stellar rotation; (3) to investigate eclipses and tidal interaction in binary systems; and (4) to search for planetary transits. Following a brief overview of the basic characteristics of the Constellation and the construction of the nanosats, I will describe the key scientific results obtained during the last 6 years, and discuss synergies with the recent TESS mission.