An astrophysicist is a scientist who specializes in studying space, stars, planets, and the universe. If you want to be an astrophysicist one day, you'll have to pay close attention in your physics class.

Today the terms astrophysicist and astronomer tend to be used interchangeably — if you make a career of being an expert on space, you'll need to know a lot about the physics of celestial bodies. The prefix astro- comes from the Greek word astron, "the stars," and physicist is rooted in physics, or "natural science," from ta physika, "the natural things" in Greek.

Definitions of astrophysicist
  1. noun
    an astronomer who studies the physical properties of celestial bodies
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    Sir Fred Hoyle
    an English astrophysicist and advocate of the steady state theory of cosmology; described processes of nucleosynthesis inside stars (1915-2001)
    Edwin Powell Hubble
    United States astronomer who discovered that (as the universe expands) the speed with which nebulae recede increases with their distance from the observer (1889-1953)
    type of:
    astronomer, stargazer, uranologist
    a physicist who studies astronomy
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