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this shows some of the layers effects scientists find so interesting , captured by the mars global surveyer , which has been in orbit since march of 1999 , one of the more successful missions nasa has ever staged to the red planet .
 nasa, scientists, the mars global surveyer, which, mars, the red planet
Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: organization, person, geographical social political, vehicle, location, weapon, facility 
Text: {0} 
Answer:
 nasa, scientists, the mars global surveyer, which, mars, the red planet