Royal Astronomical Society | Lund University | 2020 Aug 12
The question of how small, dwarf galaxies have sustained the formation of new stars over the course of the Universe has long confounded the world's astronomers. Now, an international research team has found that dormant small galaxies can slowly accumulate gas over many billions of years. When this gas suddenly collapses under its own weight, new stars are able to arise. ...
There are around two thousand billion galaxies in our Universe and, while our own Milky Way galaxy encompasses between two to four hundred billion stars, small dwarf galaxies contain only tens of thousands to a few billion stars. How stars are formed in these tiny galaxies has long been shrouded in mystery.
Now, a research team from Lund University, Sweden, has established that dwarf galaxies are capable of lying dormant for several billion years before starting to form stars again. ...
Through high-resolution computer simulations, the researchers demonstrate that star formation in dwarf galaxies ends as a result of heating and ionisation from the strong light of newborn stars across the Universe. Explosions of so-called white dwarfs -- small faint stars made of the core that remains when normal-sized stars die -- further contribute in preventing the star formation process in dwarf galaxies. ...
EDGE: From Quiescent to Gas-Rich to Star-Forming Low-Mass Dwarf Galaxies ~ Martin P. Rey et al
- Monthly Notices of the RAS 497(2):1508 (Sep 2020) DOI: 10.1093/mnras/staa1640
- arXiv.org > astro-ph > arXiv:2004.09530 > 20 Apr 2020 (v1), 10 Aug 2020 (v2)