When Luke went to look for Yoda on the planet Dagobah, he
landed/crashed quite close to Yoda's home.
This implies Dagobah is a rather small planet. I mean, if it was as big as the Earth or Mars, I guess it would be rather unlikely to
find Yoda that quickly. Luke would have to fly above the planet's surface until he either senses a force-sensitive entity (that might be a first test of how good Luke is in using the force) or Yoda made himself recognizable somehow.
I'd say Dagobah can't be much bigger than Pluto. And given the fact that it has an Earth-like surface gravity it seems to be very dense too. Dagobah's atmosphere doesn't seem to be very high either and it's fully cloudy/foggy which again implies a small and dense planet.
Wookieepedia claims the planet is 14,410 kilometers (8,954 miles) in diameter but that seems unlikely.
How would Luke find Yoda otherwise that quickly on an entire planet bigger than Earth?