ESA | Space Science | Science & Technology | Gaia | 2019 Aug 28
Rather than leaving home young, as expected, stellar ‘siblings’ prefer to stick together in long-lasting, string-like groups, finds a new study of data from ESA’s Gaia spacecraft.Gaia tracing starry strings in the Milky WayClick to play embedded YouTube video.
Credit: ESA/Gaia/DPAC; Data: M. Kounkel & K. Covey (2019);
Animation: S. Jordan / T. Sagristá / Gaia Sky – CC BY-SA 3.0 IGO
Exploring the distribution and past history of the starry residents of our galaxy is especially challenging as it requires astronomers to determine the ages of stars. This is not at all trivial, as ‘average’ stars of a similar mass but different ages look very much alike.
To figure out when a star formed, astronomers must instead look at populations of stars thought to have formed at the same time – but knowing which stars are siblings poses a further challenge, since stars do not necessarily hang out long in the stellar cradles where they formed. ...
The analysis of the Gaia data, relying on a machine learning algorithm, uncovered nearly 2000 previously unidentified clusters and co-moving groups of stars up to about 3000 light years from us – roughly 750 times the distance to Proxima Centauri, the nearest star to the Sun. The study also determined the ages for hundreds of thousands of stars, making it possible to track stellar ‘families’ and uncover their surprising arrangements. ...
Untangling the Galaxy I: Local Structure and Star Formation
History of the Milky Way ~ Marina Kounkel, Kevin Covey
- Astronomical Journal 158(3):122 (2019 Sep) DOI: 10.3847/1538-3881/ab339a
- arXiv.org > astro-ph > arXiv:1907.07709 > 17 Jul 2019 (v1), 19 Jul 2019 (v2)