Rivers and planets

We always make a fuss when we drive over rivers. It makes life more exciting, and now that we're doing school it also counts as Doing Geography.
Me: "Hey, look, Meg! It's the Shenandoah River!"
Meg: "Hey, Shenandoah! Long time no see!"
Me, speaking as the river: "Hi, Meg!"
Meg, disapprovingly: "It doesn't talk."

We're learning about planets this week. I was telling Meg how Mercury doesn't have any atmosphere, so it gets really hot during the day and really cold at night. She observed, with great accuracy, "You would have to have a spacesuit or a pair of very wooly pajamas if you wanted to sleep there."

Also on that subject: "If you had a grown-up horse [on Mercury], you would have to take care of it and put a space suit on it."

Munch, munch, said the black hole

As a star gets sucked into a black hole, it sends out an oscillation or "quasiperiodic wobble" that we can pick up on earth.

"You can think of it as hearing the star scream as it gets devoured, if you like," says the astronomer who co-authored the paper. The scream was an ultra-low D sharp.