Kepler finds exo-solar system full of ancient earth-sized worlds



Kepler, the probe that keeps on ticking, has found a well populated exo solar system of a type that could one day be the subject of a focused search by SETI — because there’s another interesting feature here: this star is very similar to our sun, it’s just a little smaller. Oh, and much, much older:

Via Email Alert — Today, in a scientific article published in Science magazine and through a NASA press conference, the Kepler team announced the discovery of a multiple planet system, composed of 5 Earth-sized and super-Earth planets orbiting a K-type star.The detection of these planets was indirect since Kepler astronomers observed the attenuation of the host star’s brightness due to the passage of a planet in the line of sight, and not the planets themselves. The authenticity of this multiple planet system was confirmed by a statistical analysis based on previous detections of multiple planets by Kepler. Details on the planets below.

“By estimating the rate of false-positives due the remote possibility of additional planet-hosting stars in the photometric aperture we have strong confidence that we have discovered two genuine transiting super-Earth planets in the habitable zone of their host star. Such calculations are only possible because of the thousands of additional transiting extrasolar planets that Kepler has discovered” said Jason Rowe, Research Scientist at the Carl Sagan Center of the SETI Institute and co-author of the work.

The outermost planet, named Kepler-62f (radius about 1.4 times Earth’s radius and a period of 267 Earth days) is located in the habitable zone of the star, a region around the star where a rocky planet with an atmosphere similar to Earth could host liquid water on its surface. The team expanded the definition of the Habitable Zone by taking into account the evolution of the brightness of the host star. Their calculations suggest that Kepler-62e (radius about 1.6 times Earth’s radius and a period of 122 Earth days) was also in the habitable zone so that liquid water could have existed on its surface, too.

Similar to Venus and Mars that are believed to have lost their surface water 1 billion years and 3.8 billion years ago respectively, before our Sun was more luminous, the host star’s habitable zone was broader in the past. The Kepler team’s calculations suggest that Kepler-62e (radius about 1.6 times Earth’s radius and a period of 122 Earth days) is also in the habitable zone so that liquid water could exist on its surface, too.

There’s another consideration, the system is 850 LYs away …. It’s times like this that speed of light seems absurdly slow. I want to see these worlds! Who wouldn’t? I want to virtually fly over their alien surfaces and soar into exotic storms. I want to dig into the rock and super-earth looking for artifacts or whatever passes for fossils there. But dammit, the best we’ll do for the foreseeable future are dancing wavy images at the limit of res and furtive spectra of sun and sat captured by titanic arrays perched on the edge of our own gravity well, and even the best of such devices are decades away if not more.


  1. says

    This is really cool and I feel exactly the same! I want to see photos of the surface. I want to go there. With so many exoplanets discovered the last decade, I’m hopeful that a habitable one will be found closer. Maybe within range of getting a better view (or communicating!)

  2. birgerjohansson says

    Odd. The source I read stated a greater distance from the sun than 850 ly. Incidentally the K dwarf has a luminosity of 20% of the sun.

    There is another system called Kepler 69. The outer of two planets orbiting a G star with 80% of the sun’s luminosity is at the innermost edge of the habitable zone.

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