University of Michigan, Ann Arbor | 2018 Oct 25
If you’re standing in the Southern Hemisphere on a clear night, you can see two luminous clouds offset from the Milky Way.
These clouds of stars are satellite galaxies of the Milky Way, called the Small Magellanic Cloud and the Large Magellanic Cloud, or SMC and LMC.
Using the newly released data from a new, powerful space telescope, University of Michigan astronomers have discovered that the southeast region, or “Wing,” of the Small Magellanic Cloud is moving away from the main body of that dwarf galaxy, providing the first unambiguous evidence that the Small and Large Magellanic Clouds recently collided. ...
Together with an international team, Sally Oey and undergraduate researcher Johnny Dorigo Jones were examining the SMC for “runaway” stars, or stars that have been ejected from clusters within the SMC. To observe this galaxy they were using a recent data release from Gaia, a new, orbiting telescope launched by the European Space Agency. ...
In looking at this data, the team also observed that all the stars within the Wing—that southeast part of the SMC—are moving in a similar direction and speed. This demonstrates the SMC and LMC likely had a collision a few hundred million years ago. ...
Resolved Kinematics of Runaway and Field OB Stars in the Small Magellanic Cloud ~ M. S. Oey et al
- Astrophysical Journal Letters 867(1):L8 (2018 Nov 01) DOI: 10.3847/2041-8213/aae892
arXiv.org > astro-ph > arXiv:1810.06596 > 15 Oct 2018 (v1), 24 Oct 2018 (v2)