In the past 25 years, planetary scientists also have studied similar data from spacecraft sent to Mars to learn how it differs from Earth in composition and origin.
(planetary scientists; have studied; similar data from spacecraft sent to Mars; T:In the past 25 years) (similar data from spacecraft; sent; to Mars; to learn how it differs from Earth in composition and origin) (similar data from spacecraft sent to Mars; to learn; how it differs from Earth in composition and origin) Context(similar data from spacecraft sent to Mars to learn,List([61, 111))):(it; differs; )
similar data from spacecraft sent to Mars to learn,List([61, 111))
planetary scientists similar data from spacecraft similar data from spacecraft sent to Mars it
have studied sent to learn differs
similar data from spacecraft sent to Mars T:In the past 25 years
to Mars to learn how it differs from Earth in composition and origin
how it differs from Earth in composition and origin