Nearest Earth-Size Planet Newly Discovered

An Earth-sized, rocky exoplanet has been discovered not that far away.

It has been named GJ 1132b and orbits a small gathering of gas (a star, that is) located about 39 light-years from Earth. It is the nearest exoplanet of our planet's size yet discovered, and is considered right in the neighborhood, galactically speaking. Astrophysicists from MIT, Harvard and elsewhere recently published their findings on it in the journal Nature.

"Our galaxy spans about 100,000 light-years," lead author Zachory Berta-Thompson of MIT said in a release. "So this is definitely a very nearby solar neighborhood star."

There are some differences between GJ 1132b and us. For instance, the newly discovered planet is hot-hot-hot and more like Venus in that respect: It is about 500 degrees Fahrenheit. It also has locked tides, meaning that one side is permanently day and one side is night, facing its star in the same way all the time. Our moon is locked in this way to the Earth, according to the release.

"Our ultimate goal is to find a twin Earth, but along the way we've found a twin Venus," said David Charbonneau of Harvard in a statement. "We suspect it will have a Venus-like atmosphere too, and if it does we can't wait to get a whiff."

Those hot temperatures probably mean that GJ 1132b cannot hold liquid water on its surface, which would make life as we know it a no-go. But scientists believe the planet is sufficiently cool to host a fairly substantial atmosphere. Also, because it's fairly near to Earth, maybe scientists will be able to learn more about its atmospheric composition, wind patterns and other details. Maybe they'll even be able to detect its sunset colors. "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," said Zachory Berta-Thompson, a postdoctoral scholar at MIT, in the release. "We finally have a target to point our telescopes at, and [can] dig much deeper into the workings of a rocky exoplanet, and what makes it tick."

The research team were able to discover the planet using the MEarth-South Observatory, which is in the mountains of Chile and is a Harvard University-led sequence of eight 40-centimeter-wide robotic telescopes. These keep an eye on nearby stars, M dwarfs. They are scattered over the night sky. While scientists know that these types of stars are often orbited by planets, they haven't yet located exoplanets of Earth's size that are near enough to study in detail. But in late spring, one of the telescopes detected GJ 1132, according to the release.

The scientists hope that others will use the James Webb Space Telecope (JWST), the successor to the Hubble Space Telescope that will be launched in 2018, to observe more characteristics of GJ 1132, the release noted.

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