On Planet Kepler 78b, A Workday Really Does Last A Year
Aug 19, 2013 11:30 AM EDT
A workday may seem like it lasts forever, but on the Earth-sized exoplanet Kepler 78b, eight hours means an entire year.
The fiery planet located about 700 light-years away has one of the shortest orbital periods ever discovered, and MIT press release reported.
The planet is located extremely close to its star, which creates a surface temperature of a scorching 5,000 degrees Fahrenheit. The extremely high temperatures melt the planet's surface, creating a ball of boiling lava.
Kepler 78b has an orbital radius of only about three times that of its star, causing it to complete an orbital "year" in 8.5 hours.
Scientists believe the star is extremely dense and made of iron at the core, in order to hold together in the intense gravitational pull from the nearby star.
"Just the fact that it's able to survive there implies that it's very dense," Josh Winn, an associate professor of physics at MIT, and co-author of two papers on the subject, said. "Whether nature actually makes planets that are dense enough to survive even closer in, that's an open question, and would be even more amazing."
Researchers discovered the short-orbit planet when going through Keppler data in search of habitable planets.
"We've gotten used to planets having orbits of a few days," Winn said. "But we wondered, what about a few hours? Is that even possible? And sure enough, there are some out there."
The scientists used a mathematical formula to pinpoint tiny dips in light created when a distant planet passes in front of a star. This led them to the discovery of Kepler 78b.
Through their calculations, the scientists determined the planet is about 40 times closer to its "sun" than Mercury. The nearby star is believed to be much younger than our galaxies' Sun, because it has a faster orbit.
The planet is most likely not habitable, due to its extremely high surface temperatures.
"You'd have to really stretch your imagination to imagine living on a lava world," Winn said. "We certainly wouldn't survive there."