this post was submitted on 19 Mar 2024
459 points (98.3% liked)

xkcd

8868 readers
16 users here now

A community for a webcomic of romance, sarcasm, math, and language.

founded 1 year ago
MODERATORS
 

https://xkcd.com/2908

Alt text:

Astronomers are a little unsure of the applicability of this index, but NASA's Planetary Protection Officer is all in favor.

you are viewing a single comment's thread
view the rest of the comments
[–] teft@lemmy.world 6 points 8 months ago

Pluto-charon shouldn't count since it is more akin to a binary planetary system than a planet-moon system. Charon and Pluto are so close in size that the system has a barycenter outside of Pluto. This means instead of Charon orbiting a point inside Pluto, Charon and Pluto orbit a point about 800 km above Pluto's surface.