<> TEXT: When NASA’s TESS mission saw hints a planet orbited the star GJ 357, astronomers rushed to confirm it.
TEXT: When they did, they also found two more planets…
ON-SCREEN TEXT: Planet labels GJ 357 b, c, and d
TEXT: …including a world astronomers are eager to learn more about.ON-SCREEN TEXT: Planet labels GJ 357 b, c, and d, and “Habitable Zone”
TEXT: TESS looks for periodic dips in starlight — called transits — to locate possible planets.
ON-SCREEN GRAPHIC: Graph with a dip in the center. X-axis: Time. Y-axis: Light.
TEXT: But they need to be confirmed using a different method.ON-SCREEN GRAPHIC: Graph with a dip in the center. X-axis: Time. Y-axis: Light.
TEXT: As a planet orbits, its gravity tugs on and slightly moves the star.
TEXT: The motion causes tiny color changes to the star’s light that telescopes on Earth can measure.
TEXT: This technique confirmed that a hot transiting planet about 22% larger than Earth orbits GJ 357: ON-SCREEN TEXT: GJ 357 b, illustration.
TEXT: It also revealed two other planets: ON-SCREEN TEXT: GJ 357 c, illustration.
TEXT: The most interesting is GJ 357 d, which may be around twice Earth’s size. ON-SCREEN TEXT: GJ 357 d, illustration.
TEXT: It receives as much energy from its star as Mars does from our Sun. ON-SCREEN TEXT: GJ 357 d, illustration.
TEXT: If it’s a rocky planet and hosts a thick atmosphere, water could flow on its surface. ON-SCREEN TEXT: GJ 357 d, illustration.
TEXT: Just 31 light-years away, a promising world beckons. ON-SCREEN TEXT: Illustration.
ON-SCREEN TEXT: EXPLORE Solar System & Beyond.