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For the first time, astronomers have detected light from planets hundreds of light years away outside the Solar System.
Infrared light was measured from two planets in distant star systems using the American space agency Nasa's Spitzer Space Telescope.
The announcement, by two separate teams in the US, marks a turning point in astronomy.
Until now the presence of extra-solar planets has only been deduced indirectly.
One method is to measure the way a planet's gravity causes its parent star to "wobble". Another is to measure the amount of "dimming" that occurs when the planet moves in front of the star.
At least 130 planets orbiting stars other than the Sun have been detected this way.
But now astronomers have directly measured the light from a pair of extra-solar planets - albeit infrared light which is invisible to the human eye.
One, catalogued as HD 209458b, is orbiting a star 153 light years from Earth in the constellation of Pegasus, the winged horse. The other, TrES-1 is an even more distant 489 light years away in the constellation Lyra.
Both were initially detected using conventional methods.
The Spitzer Space Telescope is designed to peer into regions of space normally hidden from optical telescopes by detecting infrared radiation.
taken from sky.news
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