Tuesday, 21 April 2009

KEPLER sees first light

The centuries-old quest for other worlds like our Earth has been rejuvenated by the intense excitement and popular interest surrounding the discovery of hundreds of planets orbiting other stars. There is now clear evidence for substantial numbers of three types of exoplanets; gas giants, hot-super-Earths in short period orbits, and ice giants. The challenge now is to find terrestrial planets (i.e., those one half to twice the size of the Earth), especially those in the habitable zone→ of their stars where liquid water might exist on the surface of the planet.

The Kepler Mission is specifically designed to survey our region of the Milky Way galaxy to discover hundreds of Earth-size and smaller planets in or near the habitable zone and determine the fraction of the hundreds of billions of stars in our galaxy that might have such planets.

This image zooms into a small portion of Kepler's full field of view -- an expansive, 100-square-degree patch of sky in our Milky Way galaxy. An eight-billion-year-old cluster of stars 13,000 light-years from Earth, called NGC 6791, can be seen in the image. Clusters are families of stars that form together out of the same gas cloud. This particular cluster is called an open cluster, because the stars are loosely bound and have started to spread out from each other.

The area pictured is 0.2 percent of Kepler's full field of view, and shows hundreds of stars in the constellation Lyra. The image has been color-coded so that brighter stars appear white, and fainter stars, red. It is a 60-second exposure, taken on April 8, 2009, one day after the spacecraft's dust cover was jettisoned.

Kepler was designed to hunt for planets like Earth. The mission will spend the next three-and-a-half years staring at the same stars, looking for periodic dips in brightness. Such dips occur when planets cross in front of their stars from our point of view in the galaxy, partially blocking the starlight.

To achieve the level of precision needed to spot planets as small as Earth, Kepler's images are intentionally blurred slightly. This minimizes the number of saturated stars. Saturation, or "blooming," occurs when the brightest stars overload the individual pixels in the detectors, causing the signal to spill out into nearby pixels.

Image credit: NASA/Ames/JPL-Caltech


Macko Usko said...

any news on smaller exoplanets that would be more habitable for humans

also is antigravity possible?

HooLooVoo said...

Not yet, wait a few more years. There are about 350 planets orbiting other stars discovered up to date but most are gas giants like Jupiter and very close to their host stars. For a planet to support life (as we understand it) it must be far enough from it's host star so that liquid water can exist.

If by antigravity you mean a naturally occuring phenomenon at some point in space by which the force of gravity ceases to exist or is reversed, then the answer is no. If you mean counter-balancing the effects of gravity through artificial/technological means, then yes, it is possible. Maglev trains achieve levitation through the use of superconductivity for example http://www.youtube.com/watch?v=Z4XEQVnIFmQ&feature=related