Astronomers have confirmed the discovery of the nearest rocky planet outside of our solar system.
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One of the reasons it will be so closely studied, Werner said, is because the world transits its star, meaning that the exoplanet passes in front of its star from Earth’s perspective.
Having an observable rocky planet so close to Earth (most are “hundreds of light-years away”) is like “a kind of Rosetta Stone for the study of super-Earths”, according to Michael Gillon, lead scientist for the Spitzer detection of the planet.
The planet, initially discovered using HARPS-North instrument on the Italian 3.6-metre Galileo National Telescope in the Canary Islands, is the subject of a study accepted for publication in the journal Astronomy and Astrophysics. Its existence is implied by its shadow-casting orbit by way of the glow of its solar, which was picked up by NASA’s Spitzer Space Telescope.
Now, NASA astrophysicist Natalie Batalha claimed there billions of Earth-like planets in our Milky Way Galaxy alone capable of sustaining life. The star, named HD 219134, appears quite close to the constellation Cassiopeia, a W-shaped star pattern easily seen from the northern latitudes.
Researchers can’t actually see the planet directly.
Only a small fraction of exoplanets can be detected transiting their stars due to their relative orientation to Earth.
An artist’s concept of the planet orbiting its star. While its mass and composition aren’t but decided, earlier analysis means that… The closest confirmed exoplanet is GJ674b at a 14.8 light-years away but its composition is unknown. This one is practically a next-door neighbour, ‘ said Lars A. Buchhave, an astronomer at the Harvard-Smithsonian Center for Astrophysics. The planet was determined to have a mass 4.5 times that of Earth, and a speedy three-day orbit around its star.
But HD219134b is exciting for another reason: it is the closest transiting planet known to scientists.
Follow-up studies using NASA’s Spitzer telescope showed that the new planet has a diameter 1.6 times that of Earth.
The radial velocity technique reveals the mass and orbit of a planet by measuring the strength of the gravitational tug it has on its host star.
This planet will be studied in great detail in the coming years.
The planet, likely a volcanic world of molten rock, resides in a system with two other super-Earths orbiting a bright, dwarf star.
Further observations with HARPS-North also revealed three more planets in the same star system, farther than HD 219134b.
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That star is an orange “Type K” star slightly cooler and smaller than the Sunday. And much further out, a hefty fourth world 62 times Earth’s mass orbits at a distance of 2.1 astronomical units (200 million miles) with a “year” of 1,190 days.
