How Star Formation Changes Over the History of the Universe

Astrophysicists have had to learn to be a multi wavelength observational astrophysicist. When you look with radio telescopes, you see the cold universe. If you look with visible light telescopes like Hubble, then you can see things that are a few thousand degrees in temperature. So it's really only kind of when you have this whole big pile of Legos jumbled together and you have all of them at once,. Then you can finally start putting them together into whatever it is that you're going to try to build.