508 Princetonia is a large asteroid, a type of minor planet, orbiting in the asteroid belt.

It was discovered by Raymond Smith Dugan at Heidelberg, Germany in 1903 and named "Princetonia" for Princeton University in New Jersey in the United States.

[4] Dugan found it during his time at Königstuhl Observatory with Max Wolf in Heidelberg, Germany.

[2] At the time he was working on his PhD from Heidelberg University.

The asteroid is located in the outer areas of the main asteroid belt and is about 140 km (87 mi) in diameter according to data from IRAS, an infrared space observatory in the 1980s.