Simplify the following text for a Grade 9 native English-speaking person.
Original: He discovered many small moons of Jupiter , Saturn , Uranus and Neptune , the second known Neptune Trojan , 2004 UP10 as well as several Kuiper Belt Objects , Centaurs , and Near Earth Asteroids .
Simplified: He has also discovered the second known Neptune Trojan , as well as several Kuiper Belt Objects , Centaurs , and Near Earth Asteroids .