News tagged with dark matter halos

How small can galaxies be?

Yesterday I talked about just how small a star can be, so today let's explore just how small a galaxy can be. Our Milky Way galaxy is about 100,000 light years across, and contains about 200 billion stars. Th ...

Sep 29, 2014
4.8 / 5 (26) 27

Black hole growth found to be out of sync

(Phys.org) -- New evidence from NASA's Chandra X-ray Observatory challenges prevailing ideas about how black holes grow in the centers of galaxies. Astronomers long have thought that a supermassive black hole ...

Jun 11, 2012
4.6 / 5 (9) 1 | with audio podcast

Globular clusters on a plane

Globular clusters are generally some of the oldest structures in our galaxy. Many of the most famous ones formed around the same time as our galaxy, some 13 billion years ago. However, some are distinctly ...

Sep 23, 2011
5 / 5 (1) 5

Astronomers peer into the dark

(PhysOrg.com) -- Astronomers from the Scottish Universities Physics Alliance (SUPA) have produced a completely new catalogue of ~15,000 groups of galaxies that gives a new insight into dark matter, the material ...

Apr 21, 2011
4.2 / 5 (6) 3 | with audio podcast

Halos Gone MAD

One of the successes of the ΛCDM model of the universe is the ability for models to create structures of with scales and distributions similar to those we view in the universe today. Or, at least that’s ...

Apr 08, 2011
3.5 / 5 (4) 7

Missing Milky Way dark matter

Although dark matter is inherently difficult to observe, an understanding of its properties (even if not its nature) allows astronomers to predict where its effects should be felt. The current understanding ...

Nov 09, 2010
4.9 / 5 (11) 7