This is fascinating news: 90% of the distant Universe was thought to be missing, but it was recently found. And what's weird is, it was found to be in the red. Quite literally.
[Note: before you ask, this has nothing to do with dark matter. See below!]
First, a bit of background. Galaxies are filled with hydrogen gas, and that gas is a major component of the clouds that collapse to form stars. When that happens, the hot stars ionize the gas: the flood of ultraviolet light strips the electron away from the proton, freeing both. If the electron gets near the proton again, they can recombine. Because of quantum mechanics, the electron can only exists in certain energy states, which are a bit like steps in a staircase. You can jump from the third step down to the second, but there is no second-and-a-halfth step. So it is with ...
