This artist rendition shows a planet orbiting in a binary star system.
Credit: NASA/JPL-Caltech/T. Pyle
Exoplanets are planets orbiting outside our solar system. So far, astronomers have discovered around 1,800 exoplanets, through an earnest search, applying various observation techniques. A newly discovered exoplanet orbiting in a distant star system lying 3,000 light-years away from Earth, provides new insights into the search for Earth-like or even potentially habitable planets.
At twice the mass of the Earth, the new exoplanet circles one of two stars forming a binary star system, two stars orbiting a common center of gravity. This exoplanet is separated from its parent star by a distance that is almost equal to the distance between Earth and the Sun. However, as its star is much dimmer than the Sun, it is much colder than Earth, being actually a little colder than Jupiter’s icy moon Europa.
The discovery was made by international teams of astronomers, led by professor Andrew Gould.
This finding represents the first evidence that rocky planets can form in orbits similar to Earth’s, even in a binary star system where the member stars are not widely spaced apart. But this planet itself is too cold to be hospitable for life.
“This greatly expands the potential locations to discover habitable planets in the future,” said Scott Gaudi, professor of astronomy at Ohio State. “Half the stars in the galaxy are in binary systems. We had no idea if Earth-like planets in Earth-like orbits could even form in these systems.”
Earlier evidence that exoplanets exist in binary star systems came from NASA's Kepler and Spitzer spacecrafts, but the exoplanets spotted in those observations were not similar to Earth.
References
NASA
www.nasa.gov/