What Is Dark Matter?

What we are looking at is not just stars, but galaxies full of stars. You know, when you're looking at light from as far away as you can look at your that surface,. if everything else being equal, is not flat, it's round. The whole thing is crazy. I just think about my grandparents, men. They wereb all four of em were born in the nineteenth century. And they didn't know that there was relativity - let alone what relativity would one day lead to. If we understand whatever dark matter is, what is dark energy? Suppose we figure it out, then there will be some amazing application some day, stuff we literally have yet to imagine.