International Centre for Radio Astronomy Research | 2017 Jan 17
[img3="This artist’s impression shows the spiral galaxy NGC 4921 based on observations by Hubble. Credit: ICRAR, NASA, ESA, the Hubble Heritage Team (STScI/AURA)"]http://s3-ap-southeast-2.amazonaws.com/ ... 4x1024.jpg[/img3][hr][/hr]It’s the big astrophysical whodunit. Across the universe, galaxies are being killed and the question scientists want answered is, what’s killing them?
New research published today by a global team of researchers, based at the International Centre for Radio Astronomy Research (ICRAR), seeks to answer that question. The study reveals that a phenomenon called ram-pressure stripping is more prevalent than previously thought, driving gas from galaxies and sending them to an early death by depriving them of the material to make new stars.
The study of 11,000 galaxies shows their gas -- the lifeblood for star formation -- is being violently stripped away on a widespread scale throughout the local universe.
Dark matter is the mysterious material that despite being invisible accounts for roughly 27 percent of our universe, while ordinary matter makes up just 5 percent. The remaining 68 percent is dark energy.
“During their lifetimes, galaxies can inhabit halos of different sizes, ranging from masses typical of our own Milky Way to halos thousands of times more massive,” Mr. Brown said.
“As galaxies fall through these larger halos, the superheated intergalactic plasma between them removes their gas in a fast-acting process called ram-pressure stripping. ...
Cold Gas Stripping in Satellite Galaxies: From Pairs to Clusters - Toby Brown et al
- Monthly Notices of the RAS 466(2):1275 (16 Jan 2017) DOI: 10.1093/mnras/stw2991
arXiv.org > astro-ph > arXiv:1611.00896 > 03 Nov 2016 (v1), 17 Nov 2016 (v2)