We call it dark matter because it doesn’t give off light, right? Well there is a lot of matter than doesn’t radiate, but the difference is that whatever the stuff is that we call dark matter doesn’t interact with anything through the small-scale fundamental forces.  The only way we have been able to detect it’s presence is through large-scale gravitational interaction.  Dark matter is ‘dark’ because it doesn’t interact with anything in a way that lets us figure out what it’s made of.   Well now that we’ve got that out of the way, we can look at the new...