Simplify the following text for a Grade 8 native English-speaking person.
Original: The comet 's periodicity was first determined in 1705 by English astronomer Edmond Halley , after whom it is now named .
Simplified: The comet is named after Edmond Halley ( 1656 -- 1742 ) , an English astronomer , who predicted the comet 's return . Halley 's Comet was the first comet to be recognized as periodic .