A Canadian scientist says helping NASA with a mission to Mars to look for signs of life is the fulfillment of a childhood dream.
Herd says Perseverance, the latest Mars rover, is being sent to an ancient lake bed on a theory that such spots are most likely to contain signs of life.
The Perseverance is to be launched Thursday.
Herd says he first began dreaming about working with rocks from Mars when he was 13 years old.
NASA plans to return to Mars to retrieve samples left by Perseverance in about a decade.