The chunks of comet Shoemaker-Levy 9 were so large, and were moving so fast, that each hit Jupiter with at least the equivalent energy of the dinosaur-killing collision between Earth and an asteroid 65 million years ago. Whatever damage Jupiter sustained, one thing is for sure: it's got no dinosaurs left.

It turns out that the history of astrophysics is where we perfected time keeping.

I love the future we might invent for ourselves that I have not yet dreamt of.

But my vote for Venus's most peculiar feature is the presence of craters that are all relatively young and uniformly distributed over its surface. This innocuous-sounding feature implicates a single planetwide catastrophe that reset the cratering clock... turning Venus's entire surface into the American automotive dream-a totally paved planet.

People like it when they understand something that they previously thought they couldn't understand. It's a sense of empowerment.

Just before I said I wanted to be an astronomer I said I wanted to be a baseball player. I was quite athletic at the time, probably because I was bigger than other kids, and if you're bigger than other kids and you're 11 you win everything.

We're talking about a being whose very existence challenges our own sense of priority in the universe.