74830
Its main ring contains knots of nebulosity , which have now been detected in several nearby planetary nebulae , especially those with a molecular envelope like the Ring nebula and the Dumbbell Nebula .
 astronomical object: Ring nebula; astronomical object: Dumbbell Nebula
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: Ring nebula, Dumbbell Nebula 
Answer:
 astronomical object: Ring nebula; astronomical object: Dumbbell Nebula