Scientists have found a new kind of alien planet - a steamy waterworld which is larger than Earth but small compared to Uranus.
The standard-bearer because of this new class of exoplanet is named GJ 1214b, which astronomers first discovered in December 2009. New observations by NASA's Hubble Space
Telescope declare that GJ 1214b is a watery world enshrouded with a thick, steamy atmosphere.
"GJ 1214b is similar to no planet we realize of," study lead author Zachory Berta with the Harvard-Smithsonian Center for Astrophysics in Cambridge, Mass., said in the statement. "A huge fraction of the mass comprises of water."
Up to now, astronomers have discovered greater than 700 planets beyond our solar system, approximately 2,300 more "candidates" awaiting confirmation by follow-up observations.
"GJ 1214b is similar to no planet we realize of," study lead author Zachory Berta with the Harvard-Smithsonian Center for Astrophysics in Cambridge, Mass., said in the statement. "A huge fraction of the mass comprises of water."
Up to now, astronomers have discovered greater than 700 planets beyond our solar system, approximately 2,300 more "candidates" awaiting confirmation by follow-up observations.
These alien planets certainly are a diverse bunch. Astronomers have discovered one planet as light and airy as Styrofoam, as an example, and another as dense as iron. They've discovered several alien worlds that orbit two suns, like Luke Skywalker's home planet of Tatooine inside the "Star Wars" films. [The Strangest Alien Planets]
But GJ 1214b, which is located 40 light-years from Earth in the constellation Ophiuchus (The Serpent Bearer), is something new altogether, researchers said.
This so-called "super-Earth" is all about 2.7 times Earth’s diameter and weighs nearly seven times just as much as our home planet. It orbits a red-dwarf star well away of 1.Two million miles (Two million kilometres), passing on an estimated surface temperature of 446 degrees Fahrenheit (230 degrees Celsius) - too hot to host life as you may know it.
Scientists first reported this year that GJ 1214b's atmosphere is probably going composed primarily water, but their findings are not definitive. Berta and the team used Hubble's Wide Field Camera 3 to aid dispel the doubts.
Hubble watched as GJ 1214b crossed facing its host star, and also the scientists could actually determine the composition with the planet's atmosphere for the way it filtered the starlight.
"We’re using Hubble to look at the infrared hue of sunset about this world," Berta said. "The Hubble measurements really tip the check in favor of a steamy atmosphere."
Berta and the colleagues report their results online within the Astrophysical Journal.
A watery world
Berta and the colleagues report their results online within the Astrophysical Journal.
A watery world
Since astronomers know GJ 1241b's mass and size, they can calculate its density, which happens to be just 2 grams per cubic centimeter (g/cc). Earth's density is 5.5 g/cc, that is one of water is 1 g/cc.
GJ 1214b thus seems to have much more water than Earth does, and far less rock. The alien planet's interior structure is probably quite different from that relating to our world.
"The high temperatures and pressures would form exotic materials like 'hot ice' or 'superfluid water,' substances which are completely alien to your everyday experience," Berta said.
GJ 1214b probably formed farther out from its star, where water ice was plentiful, and then migrated in to its current location long ago. In the process, it would have experienced more Earth-like temperatures, but how long this benign phase lasted is unknown, researchers said.
Because GJ 1214b is so close to Earth, it's a prime candidate for study by future instruments. NASA's James Webb Space Telescope, which is slated to launch in 2018, may be able to get an even better look at the planet's atmosphere, researchers said.
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