Science April 11, 2018 Scientists Found a Galaxy With Almost No Dark Matter. Here’s What That Means.A galaxy known as DF2 contains almost no dark matter, challenging what researchers thought they knew about how galaxies form.Source: Scientists Found a Galaxy With Almost No Dark Matter. Here’s What That Means.Share this:WhatsAppTweetEmailRelated AstronomySpace
Dark matter fills ’empty’ space, strongly interacts with visible matter and is displaced by visible matter.
The reason for the mistaken notion the galaxy is missing dark matter is that the galaxy is so diffuse that it doesn’t displace the dark matter outward and away from the galaxy to the degree that the dark matter is able to push back and cause the stars far away from the galactic center to speed up.
It’s not that there is no dark matter connected to and neighboring the visible matter. It’s that the galaxy has not coalesced enough to displace the dark matter to such an extent that it forms a ‘halo’ around the galaxy.
A galaxy’s halo is not a clump of dark matter traveling with the galaxy. A galaxy’s halo is the state of displacement of the dark matter.