When Harvard graduate student Zachory Berta ’07 first spotted the planet known as GJ 1214b, it was just a tiny blip dimming the light from a star in the Ophiuchus constellation. But the blip passed the star regularly — every 1.6 days. Berta and his colleagues at the Harvard-Smithsonian Center for Astrophysics’ MEarth Project, led by professor David Charbonneau, soon confirmed that it was a planet, a “super-Earth” located 40 light-years away. (A super-Earth is a planet between one and ten times the mass of the Earth.)
“It was exciting,” Berta told PAW. “I was half optimist, half skeptic up until that point.” The discovery, made in May and published last week in the journal Nature, has earned headlines in The New York Times, Time, and hundreds of other news outlets.
There are more than 400 known planets outside our solar system, so finding a new one is not always big news. But GJ 1214b is notable for several reasons: It is relatively small (2.7 times the size of Earth), it’s likely to have water on its surface, and future studies may confirm that it is the first super-Earth with an atmosphere (though, as Charbonneau said in a news release, “that atmosphere probably won’t be hospitable to life as we know it”; the astronomers estimate the planet’s temperature to be about 400 degrees Fahrenheit).
The new super-Earth also is relatively close to our solar system, and the Harvard team has made a proposal for additional study, using NASA’s Hubble Space Telescope. “It’s an ideal system to follow up with,” Berta said. “We can learn a lot more [about GJ 1214b].”
Berta is now in his second year as a Ph.D. student, and his interest in astrophysics as a career began at Princeton, where he studied under renowned researchers like David Spergel ’82. For his senior thesis, Berta mapped clusters of galaxies, using images from the Sloan Digital Sky Survey. He wrote about the project in the July 18, 2007, issue of PAW.
(Photo by Frank Wojciechowski)
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