Gaia 8: Discovery of a star cluster containing β Lyrae

Abstract

Aims. The aim here is to try and clarify whether there are stars in the neighbourhood of β Lyrae which are physically connected to the famous prototype eclipsing binary. Methods. We scrutinised the astrometric and photometric data (from HIPPARCOS and Gaia DR2) of stars in a limited sky field around β Lyrae. Results. A star cluster of about 100 members was discovered, nicely centred on β Lyrae in five dimensions. There are clear indications that the newly discovered cluster belongs to a larger old (extinct) star formation complex, including two known star clusters and an extended, strewn field of stars at practically the same distance and space velocity. Conclusions. This discovery opens up the possibility of determining a precise distance and precise age for β Lyrae using the combined properties of the cluster members. This in turn may form an important basis for an improved astrophysical interpretation of the model binary β Lyrae and its kin. The larger old star formation complex is of scientific interest in its own right.