60547
By 1803 , he had observed changes in the relative positions in a number of double stars over the course of 25 years , and concluded that they must be binary systems ; the first orbit of a binary star , however , was not computed until 1827 , when Félix Savary computed the orbit of Xi Ursae Majoris .
 Félix Savary, Xi Ursae Majoris
Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: media, plant, vehicle, astronomical object, time, disease, animal, location, person, organization, mythical figure, food, biology, geographical phenomenon, instrument, event 
Text: {0} 
Answer:
 Félix Savary, Xi Ursae Majoris