Scientists using NASA’s Kepler telescope have identified eight new exoplanets in the Goldilocks zone of their parent stars. Goldilocks zone is the distance of an exoplanet from its parent star where liquid water can exist on the planet’s surface. Two of them are the most similar to the Earth of any known planet to date. Finding of the Earth’s closest twins was described at the American Astrological Society meeting in Seattle.
How do they resemble Earth?
The two most Earth-like planets are Kepler-438b and Kepler-442b. They are orbiting red dwarf stars that are dimmer and smaller than our Sun. Kepler-438b is 12% bigger than Earth in diameter. It receives about 40% more light than our planet. Scientists say that it has 70% chance of being rocky. This exoplanet is 470 light years away from the Earth. By comparison, Venus receives twice as much light as Earth.
Kepler-442b is about 33% bigger than Earth, and gets 66% as much light as Earth. It has 60% chance of being rocky. Researchers said it has 97% chance of being in the habitable zone. Kepler-442b is 1,100 light years away from our planet. Before the discovery of these two exoplanets, Kepler-186f and Kepler-62f were considered two most Earth-like planets.
Kepler has identified over 1,000 confirmed planets
So far, NASA’s Kepler telescope has identified over 1,000 confirmed planets and 4,75 possible candidates outside the solar system. Lead author Guillermo Torres of the Harvard-Smithsonian Center for Astrophysics said that it was still unclear whether any of these candidates were truly habitable. That’s because most of the candidates, including the newly discovered ones, are so distant that additional observations become challenging.
The planets were far too small to confirm their masses by measuring. So, researchers validated them by using a computer program called BLENDER. It runs on the Pleiades supercomputer at Nasa Ames. The $600 million Kepler was launched in 2009 to find Earth-like exoplanets around the Milky Way galaxy.