One of the coolest things ever is you can see the shadows and depths of the craters on the moon from here on Earth, with a cheap ~$15 telescope or probably binoculars too. I remember buying the galileoscope for $15 many years ago and was absolutely shocked how cool the moon looked, and how 3D.
Pro-tip: the full moon isn't so fun to look at, you want some level of crescent moon so you can avoid getting overloaded on the brightness.
(You can also stay up for a few hours and actually observe Io revolving around Jupiter, I think it takes most of the night to get 1/4 of the way around. Pretty obvious revolutions when you keep observing throughout the night.)
Pro-tip: the full moon isn't so fun to look at, you want some level of crescent moon so you can avoid getting overloaded on the brightness.
(You can also stay up for a few hours and actually observe Io revolving around Jupiter, I think it takes most of the night to get 1/4 of the way around. Pretty obvious revolutions when you keep observing throughout the night.)