The newly discovered planet is 16 percent larger than Earth, and it is made of rock and metal like our own planet. However, scientists say it is not likely to host life as we know it.

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A small planet, just a bit bigger than Earth, has been detected in our stellar neighborhood, just 39 light-years away.

Known as GJ 1132b, it is the closest rocky exoplanet to have been found, and astronomers say it could provide our most in-depth look yet at an alien world not so different from our own. The official term for a planet outside our solar system is exoplanet.

Drake Deming, an astronomer at the University of Maryland who was not part of the study, was so excited about the findings, published this week in Nature, that he described the new world as “arguably the most important planet ever found outside the solar system” in an accompanying News and Views article.

The newly discovered planet is 16 percent larger than Earth, and it is made of rock and metal like our own planet. However, scientists say it is not likely to host life as we know it.

Its small, dim, sun is one-fifth the size of our own sun, but GJ 1132b circles it at a distance of just 1.4 million miles, completing a full orbit once every 1.6 Earth days. (For perspective, Mercury orbits the sun from a distance of 36 million miles.)

The exoplanet’s proximity to its host star keeps its temperature at a broiling 500 degrees Fahrenheit, about as hot as the highest setting on your home oven, said Zachory Berta-Thompson, a postdoctoral student at the Massachusetts Institute of Technology’s Kavli Institute for Astrophysics and Space Research.

At that temperature, liquid water cannot exist on the planet’s surface, although scientists say it is likely the planet has an atmosphere.

“Our best guess is that this planet looks like Venus,” said Berta-Thompson, who was also the first author on the study. “But we won’t have to guess for long. This is the first rocky planet for which we have the chance to go out and observe its atmosphere.”

While the scientists say the planet is too hot for life, it’s still much cooler than the rocky fireballs known to orbit stars beyond our solar system. “If we find this pretty hot planet has managed to hang onto its atmosphere over the billions of years it’s been around, that bodes well for the long-term goal of studying cooler planets that could have life,” Berta-Thompson said.

Another author, astronomer David Charbonneau of the Harvard-Smithsonian Center for Astrophysics, said: “Our ultimate goal is to find a twin Earth, but along the way we’ve found a twin Venus.”

GJ 1132b was discovered with the help of the MEarth-South Observatory, a Harvard University array of eight 16-inch wide robotic telescopes stationed in the mountains of Chile. The array is specifically tasked with looking among nearby stars exoplanets that in some way resemble Earth.

“The idea is if we can find the planet in a small telescope, we can study it in much more detail with a large telescope,” Berta-Thompson said.

The researchers first detected GJ 1132b in May 2014, when they noticed a telltale dip in the brightness of a small red dwarf star that suggests a planet had passed in front of it, blocking some of its light.

After confirming the finding with other telescopes, the researchers proceeded to do a series of measurements and calculations to characterize the exoplanet.

Berta-Thompson said the initial investigations of the newly found planet are just the beginning of what he hopes will be a lot more studies, especially once the powerful James Webb Space Telescope is launched in October 2018.

“We’ve come up with theories about rocky planets — how they formed, how they got into their current orbits, what physical processes occur on them — but we have not been able to test many of them,” he said. “The discovery of this planet gives us the opportunity to switch our focus from imagining what is out there to testing our theories observationally.”