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What is the person who studies the heavenly bodies?
Well, Depending on you question.: Either 1: The Photographer who works at PlayBoy Magazine. or 2: Astronomer. A man works looks at the stars and moons and planet in the universe.
Astronomers use many instruments including many different types of telescopes, radio telescopes, infra red detectors, microwave antennae, gamma ray detectors, nutrino detectors buried deep in mines...