A new type of planet

• Essentially one big ocean, GJ 1214b orbits a red dwarf star in this artist's conception. 
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  Researchers now believe the "water world" represents an new type of planet. (David A. Aguilar, CfA)
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  Nasa's Hubble Space Telescope has confirmed the existence of a completely new type of planet.
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  By analyzing the previously identified world GJ 1214b -- an Earth-like superplanet located outside of our solar system -- astronomer Zachory Berta and his team have discovered a strangely unique water-based planet.
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  When it comes to planets, our solar system contains three distinct types: rocky and terrestrial like Mars and Earth, gas giants such as Jupiter and Saturn, and ice giants like Uranus and Neptune.

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GJ 1214b, researchers soon realized, was none of the above.
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GJ 1214b is like no planet we know of, said Berta, who hails from the Harvard-Smithsonian Center for Astrophysics. 
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A huge fraction of its mass is made up of water.

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If you want to describe in one sentence what this planet is, it’s a big, hot ocean,” Harvard University astronomer David Charbonneau told Wired in 2009 when the planet was first discovered by the MEarth Project, an NSF-funded, robotic observatory in Arizona.

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It might have life, but it would have to be a strange kind of life.

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Since the planet is too far to be seen directly, researchers have had to infer its presence and characteristics from subtle distortions in light. 

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As such, Berta and his crew have only recently been able to determine the planet’s steamy atmosphere.

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We’re using Hubble to measure the infrared color of the sunset on this world. 
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The spectrum of GJ 1214b to be featureless across many colors, a model consistent with a dense atmosphere composed of water vapor.

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The Hubble measurements really tip the balance in favor of a steamy atmosphere.

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The result is a water world very different to our own, one where the atmosphere is roughly ten times thicker creating extreme atmospheric pressures with little light getting through.

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The high temperatures and high pressures would form exotic materials like ‘hot ice’ or ‘superfluid water’ -- substances that are completely alien to our everyday experience.

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Life too, if it exists, will certainly be weird.

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We don’t want to imply that there’s any indication of life as we know it. 
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It might have life, but it would have to be a strange kind of life.

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This planet will occupy scientists for years. 
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That’s part of what’s so exciting.