55583
On 6 October 1995 , Michel Mayor and Didier Queloz of the University of Geneva announced the first definitive detection of an exoplanet orbiting a main-sequence star , nearby G-type star 51 Pegasi .
 person: Michel Mayor; person: Didier Queloz; organization: University of Geneva; astronomical object: 51 Pegasi
Given options, please tell me the categories of all the listed entity words.Output format is "type1: word1; type2: word2". 
Option: media, plant, vehicle, astronomical object, time, disease, animal, location, person, organization, mythical figure, food, biology, geographical phenomenon, instrument, event 
Text: {0} 
 Entities: Michel Mayor, Didier Queloz, University of Geneva, 51 Pegasi 
Answer:
 person: Michel Mayor; person: Didier Queloz; organization: University of Geneva; astronomical object: 51 Pegasi