37737
This was the view expressed in the 6th century by the astronomers Varāhamihira and Bhadrabahu , and the 10th - century astronomer Bhaṭṭotpala listed the names and estimated periods of certain comets , but it is not known how these figures were calculated or how accurate they were .
 Varāhamihira, Bhadrabahu, Bhaṭṭotpala
Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: location, person, organization 
Text: {0} 
Answer:
 Varāhamihira, Bhadrabahu, Bhaṭṭotpala