Graphing variables is a critical skill in science. If something depends on something else -- like the speed of sounds depends on air density, or the surface gravity of an object depends on its size -- then if you plot the two things on a graph, you should see a pattern. The result is a line, or a curve. If the two things don't depend on each other, you get a random collection of dots: a scatter plot. About a hundred years ago, two astronomers plotted the brightness of stars against their color (from blue to red) and what they found was amazing: a clear connection between the two! In fact, stars fell into several groups, and over the years we've learned about why that happens. Most stars are stable, like the Sun, and fall into the Main Sequence of the plot. Some are old, some young, some dying, some dead. And they all have their place in what we now call the Hertzsprung-Russel diagram, or H-R diagram for short. It's one of the most useful tools astronomers have ever created. And now my friend Stuart who runs Astronomy Blog has done it one better: he's created an H-R diagram of media stars. It's awesome:

That's really funny, and I wish I had thought of it. The vertical axis is fame, as denoted by Google results, and the horizontal axis is peer-reviewed papers. I'm actually only first author on I think two papers, but I was listed as author on a lot due to my work on Hubble. So I do OK on this diagram. I note that Brian Cox is more luminous than me, but then, he's an actual rock star. If there were a branch for white main sequence stars, he and I would be in a dead heat. Next up, I hope: a space-time diagram showing warping due to massive astronomers.