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Astronomers spot an Earth-like planet orbiting a sun-like star

Astronomers have located a planet and star which are more similar to Earth and the sun than any pair found before. Located around 3000 light-years away, the star Kepler-160 and its orbiting planet KOI-456.04 are close enough together that there could even be liquid water on the planet’s surface.

The discovery was made by researchers from the Max Planck Institute for Solar System Research (MPS) in Germany, investigating a star first observed by NASA’s Kepler space telescope. Research conducted in 2010 suggested that Kepler-160 could have two exoplanets orbiting around it. Now, the researchers believe that the star in fact hosts three or even four exoplanets, including the Earth-like KOI-456.04.

An artist’s depiction of an Earth-like exoplanet. NASA/JPL-Caltech/T. Pyle

Most exoplanets discovered thus far are bigger than Earth, at around four times it size or approximately the same size as Neptune, and they typically orbit relatively close to their stars. But occasionally, astronomers spot a potentially rocky planet around the size of the Earth. These are often orbiting red dwarf stars, however, which only give off faint radiation, making the planet uninhabitable.

What makes KOI-456.04 special is not only the fact it is comparably sized to Earth, at less than twice its size, but also that its star is similar to our sun and that it orbits at an almost identical distance as Earth does. This means it could potentially be the right temperature to have liquid water on its surface.

Even if KOI-456.04 were to host liquid water though, don’t plan on moving there just yet. Other factors go into habitability, such as whether the planet has an atmosphere, which can have a profound effect on its surface temperatures. However, the potential for the planet is still impressive.

“The surface conditions on KOI-456.04 could be similar to those known on Earth, provided its atmosphere is not too massive and non-Earth-like,” the MPS wrote in a statement. “The amount of light received from its host star is about 93% of the sunlight received on Earth. If KOI-456.04 has a mostly inert atmosphere with a mild Earth-like greenhouse effect, then its surface temperature would be +5 degrees Celsius on average, which is about ten degrees lower than the Earth’s mean global temperature.”

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Georgina Torbet
Georgina is the Digital Trends space writer, covering human space exploration, planetary science, and cosmology. She…
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