Abstract

The A5 dwarf star β Pictoris has been subject of numerous studies because it addresses several questions of stellar astrophysics, like stellar evolution, circum-stellar disks, planet formation and pulsations. With V = 3.86 mag, it falls within the observable magnitude range of BRITE and is a promising target for this space mission. Evolutionary stage One of the open questions is the evolutionary stage of β Pic. Latest age determinations agree to 20±10 million years (e.g., Barrado y Navascues et al. 1999), but with an upper limit of a factor of 10 more. From its position in the Hertzsprung-Russell (HR) diagram (e.g., Vidal-Madjar et al., 1998) it is right on the zero-age main sequence or slightly before. In other terms, β Pic is either a pre-main sequence (PMS) object or a young main sequence star. The debate about its evolutionary stage is still ongoing, but there are indications for the early main sequence phase: the star shows no emission lines in its