In what sounds like an astronomical “David and Goliath” tale, the smallest planet in the solar system (no, not Pluto, the other one) has helped astronomers precisely measure the width of the largest thing in the solar system — the sun.
Wait. I hear you cry. Do astronomers have nothing better than to measure the girth of our nearest star? Besides, we should know that already… shouldn’t we?
In the sage words of Bad Astronomer Phil Plait: “Sometimes the simplest things can be the hardest, I suppose.” And he’d be right.