Dynamical studies of nearby young stellar populations

Description:

The night sky surrounding the South Celestial Pole hosts several young, pre-main sequence stellar associations with ages ranging from approximately 1-20 million years, that are relatively close to the Sun at distances of 50-150 parsecs. A number of these systems have either been discovered or have been characterised by UNSW Canberra astronomers. Some of these groups are believed to be outlier populations of the massive Scorpius-Centaurus-Ophiuchus OB-star association, which is the closest large star forming complex to the Sun.

While the dynamical state of these systems has been studied in several publications, in most cases the 3D nature of these systems is either ignored or has had to be inferred. However, the Gaia satellite launched in 2013 and expected to be in operation until 2025 is designed for astrometry, measuring the distances, positions, and space motions of stars with extraordinary precision. Gaia astrometry has the precision to resolve these nearby young systems in three dimensions, permitting the study of their 3D structure. 

The project is to use Gaia astrometry to study one or more nearby young stellar associations. Many of the fundamental stellar properties of the individual stars of these associations are known in detail and these data will be used to enhance the Gaia results; these include study of the radial mass, radial disk, and radial binary fraction of the associations.