BRITE-Constellation: nanosatellites for precision photometry of bright stars

TL;DR

BRITE-Constellation is an international nanosatellite mission designed to perform high-precision, multi-colour photometry of bright stars, enabling detailed asteroseismology, surface activity studies, and planetary transit searches.

Contribution

It introduces a novel nanosatellite constellation capable of continuous, precise photometric monitoring of bright stars in two colours, which was not feasible from ground-based observations.

Findings

Successful deployment of six nanosats with wide-field optical telescopes.

Ability to observe up to 15 bright stars simultaneously in two colours.

Enhanced data collection for stellar pulsations, surface activity, and exoplanet transits.

Abstract

BRITE-Constellation (where BRITE stands for BRIght Target Explorer) is an international nanosatellite mission to monitor photometrically, in two colours, the brightness and temperature variations of stars generally brighter than mag(V) ~ 4, with precision and time coverage not possible from the ground. The current mission design consists of six nanosats (hence Constellation): two from Austria, two from Canada, and two from Poland. 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 15 bright stars can be observed simultaneously, sampled in 32 pixel x 32 pixel sub-rasters. Photometry of additional fainter targets, with reduced precision but thorough time sampling, will be possible through onboard data processing. The BRITE sample is dominated by the most intrinsically luminous stars: massive stars seen at all evolutionary stages, and evolved medium-class stars at the very end of their nuclear burning phases. The goals of BRITE-Constellation are to (1) measure p- and g-mode pulsations to probe the interiors and ages of stars through asteroseismology; (2) look for varying spots on the stars surfaces carried across the stellar disks by rotation, which are the sources of co-rotating interaction regions in the winds of the most luminous stars, probably arising from magnetic subsurface convection; and (3) search for planetary transits.