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January 11, 2011

NASA Finds First Rocky World Outside Our Solar System

From NASA.gov:

NASA's Kepler mission confirmed the discovery of its first rocky planet, named Kepler-10b. Measuring 1.4 times the size of Earth, it is the smallest planet ever discovered outside our solar system.

The discovery of this so-called exoplanet is based on more than eight months of data collected by the spacecraft from May 2009 to early January 2010.

"All of Kepler's best capabilities have converged to yield the first solid evidence of a rocky planet orbiting a star other than our sun," said Natalie Batalha, Kepler's deputy science team lead at NASA's Ames Research Center in Moffett Field, Calif., and primary author of a paper on the discovery accepted by the Astrophysical Journal. "The Kepler team made a commitment in 2010 about finding the telltale signatures of small planets in the data, and it's beginning to pay off."

Kepler's ultra-precise photometer measures the tiny decrease in a star's brightness that occurs when a planet crosses in front of it. The size of the planet can be derived from these periodic dips in brightness. The distance between the planet and the star is calculated by measuring the time between successive dips as the planet orbits the star.

Kepler is the first NASA mission capable of finding Earth-size planets in or near the habitable zone, the region in a planetary system where liquid water can exist on the planet's surface. However, since it orbits once every 0.84 days, Kepler-10b is more than 20 times closer to its star than Mercury is to our sun and not in the habitable zone.

Kepler-10 was the first star identified that could potentially harbor a small transiting planet, placing it at the top of the list for ground-based observations with the W.M. Keck Observatory 10-meter telescope in Hawaii.

Scientists waiting for a signal to confirm Kepler-10b as a planet were not disappointed. Keck was able to measure tiny changes in the star's spectrum, called Doppler shifts, caused by the telltale tug exerted by the orbiting planet on the star.

The rest of the article is on http://www.nasa.gov/topics/universe/features/rocky_planet.html

So, even though the planet is hotter than flowing lava.. 2500˚ F, NASA was still happy.

The program scientist says, "The discovery of Kepler-10b, a bona fide rocky world, is a significant milestone in the search for planets similar to our own.”

Good stuff

Posted by aarthi at January 11, 2011 05:07 PM


This is an awesome find! I think it is very cool that we have finally found something somewhat similar to Earth in that it will help us on our mission to search for life outside of our own universe. I believe this discovery could lead to great new finds in the world of astrobiology and so on. I cannot wait to hear more about Kepler-10!

Posted by: alysalev at January 11, 2011 09:32 PM

If Kepler-10 is considered the smallest planet found outside of our solar system, but it's 1.4 times the size of the Earth, then it reinforces just how amazing the Universe is and how Earth isn't necessarily as special as people may think.

Posted by: brdoss at January 12, 2011 09:21 AM

I posted an article similar to this one! It appears as if there's been some updates from the article I read. Interesting stuff. As I was reading it was hard for me to really understand what the significance of this find was. It actually took me a couple read-throughs before I was able to understand. I can see that for a true astronomer this is a remarkable find, but it's pretty mind-boggling to try and comprehend. From what I read it sounds like most of the excitement is coming from scientists ability to measure the density of this planet, which in turn gives us information about its rocky surface. This one tiny similarity seems so insignificant, especially for a planet whose temperature is almost that of the melting point of iron.

Posted by: kailjoyb at January 12, 2011 09:54 PM

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