This artist's conception illustrates Kepler-22b, a planet known to comfortably circle in the habitable zone of a sun-like star. (Image: NASA/Ames/JPL-Caltech)

Artist's conception of Kepler-22b, a planet which circles a sun-like star. (Image: NASA/Ames/JPL-Caltech)

A newly-discovered Earth-like planet could very well contain continental features where normal human-like life could exist. Or it  could be more of a water world with an ocean containing life forms similar to dolphins.

That’s according to Dr. Alan Boss, of the Carnegie Institution for Science, one of the researchers involved in  discovering the new planet.

This past Monday, NASA announced that its Kepler space telescope confirmed the first planet orbiting a star in its “habitable zone,” the region where liquid water could exist on a planet’s surface.

Some scientists described this planet, known as Kepler 22B, as “Earth-like” with a star similar to our sun.

Located some 600 light-years away, Kepler 22B is about 2.4 times the radius of Earth.  And while scientists don’t yet exactly know if the planet is predominantly rocky, gaseous or liquid composition, its discovery has excited  scientists who now say we’re now one step closer to finding other Earth-like planets throughout the cosmos.

If it is truly made of rock, as some speculate, Dr. Boss says it might look something like our own Earth with probably a fair amount of water on it as well.

This diagram compares our own solar system to Kepler-22, a star system containing the first "habitable zone" planet discovered by NASA's Kepler mission. (Image: NASA/Ames/JPL-Caltech)

While Kepler 22B is larger than Earth, its orbit of 290 days around a sun-like star resembles that of our world.  The planet’s host star belongs to the same class as our sun, called G-type, although it is slightly smaller and cooler.

Because of it star’s cooler attributes, Kepler 22B’s orbit is much closer to it in order to be habitable.  Dr. Boss says, with an atmosphere similar to ours, Kepler 22B’s surface temperature would be close to 72 degrees Fahrenheit, like a “rather pleasant day on Earth, a nice spring day.”

Dr. Boss credits the 2009 launch of NASA’s Kepler Space Telescope with the discovery.  He calls Kepler, “NASA’s most important mission to try to find planets around other stars.”

The Kepler mission does this by staring at a field of 150,000 stars – in the constellations of Cygnus and Lyra – and watching to see if any of those stars “blink”.

According to Dr. Boss, if the telescope finds a star blinking repetitively, it can sometimes be inferred that there is something passing in front of it, such as a planet orbiting around the star.

Artist's concept of the Kepler Space Telescope in space (Image: Dana Berry-NASA/Kepler Mission)

Artist's concept of the Kepler Space Telescope in space (Image: Dana Berry-NASA/Kepler Mission)

Boss says this  dimming of the star can be hard to detect, which is why observations must be made from space rather than from an Earth observatory.

The Kepler team has identified 48 other planet candidates, which can be found in their star’s habitable zone.  Further investigation needs to be done before any can actually be confirmed discoveries.

Dr. Boss joins us this weekend on the radio edition of “Science World.”  He gives us an insider’s view of  the remarkable discovery, as well as the search for habitable alien worlds. Tune in (see right column for scheduled times) or check out the interview below.

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Watch NASA’s Kepler Mission Announces Latest Planetary Discovery

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