Pop physics

So a breakdown of the graph: The little blueish slice there is the stuff we can see. All the stars and galaxies and everything that emits light is accounted for in that slice. And it’s a pretty small slice. The orange slice is the interstellar gas. This is the stuff that the stars form from. It’s mostly hydrogen and helium, and some carbon and bits of heavier elements. It floats around the universe and sometimes collapses to form stars (I’ve included a picture of some gas backlit by some stars). And the speckley grey stuff is obviously dark matter. It’s the stuff that contributes to gravity to hold the universe in the precarious balance that it sits in. And the rest is dark energy. And there sure it a lot of it. I’ve always found this graph amazing. All the stuff we’ve ever been impressed with or looked at or awed at is only the tiniest fraction of all the ‘stuff’ in the universe. That’s just nuts!