Astrophysicists have discovered a new type of planet — a “hot ice” water world with a thick, steaming atmosphere.
For a while, they called it “Kevin”.
The name didn’t stick. Even in his mind, Zachory Berta, the Harvard University grad student who discovered the planet and has now classified its uniqueness, “Planet Kevin” is called GJ1214b.
“Kevin” was after actor Kevin Costner who starred in the 1995 flick, Waterworld.
“GJ1214b is like no planet we know of,” Berta said. “It’s hot and has a lot of water.”
The new planet, 2.7 times bigger than Earth, had been discovered orbiting a red dwarf star in 2009 by Berta and his thesis adviser David Charbonneau of the Havard Smithsonian Center for Astrophysics.
Almost immediately, Berta started calculating what its atmosphere could be made of. But until NASA’s Hubble Space Telescope was equipped with the Wide Field Camera 3 during the last shuttle trip, he couldn’t really nail it down.
GJ1214b has a density of about 2 grams per cubic centimetre, Berta said, far less than earth’s average density of 5.5 grams. Water has a density of 1 gram per cubic centimetre.
Through meticulous calculations, “we’ve excluded any of the astronomically plausible things that don’t have a lot of water” to figure out what GJ1214b is made of.
The water world sits in the constellation Ophiuchus about 40 light years from Earth. Details of the findings by Berta and an international team are reported in the Astrophysics Journal.
The next advance to help astronomers study atmospheres will be the James Webb Telescope, to be launched in 2018, said Berta.
He is convinced that within a decade, or two at the most, astronomers will have found an Earthlike planet, something a little cooler and smaller than GJ1214b, that “could conceivably have life thriving on it.
“That’s the cool thing about astronomy. As we build bigger telescopes, we can find more of these planets.”
As more are found, astronomy really has to start naming these planets, including “our little planet” GJ1214b, said Berta.
“People need something to latch on to. I don’t want it to be Kevin.”
What about an astronomer that has inspired him?
“Annie Jump Cannon, who gave us the name of the type of star we’re studying.”
The pioneering Harvard Observatory astronomer created the classification system for more than a quarter-million stars in the early years of the 20th century.