Scientists have detected light emanating from a super-earth planet and they believe that the finding is a major step towards the search for signs of life on other planets.
Nasa scientists have discovered a mysterious planet, 55 Cancri e, relatively close to earth at 41 light-years away. They found mysterious light emanating from 55 Cancri e with the help of Nasa's Spitzer Space Telescope, which has special heat-seeking infrared vision.
Scientists discovered the mysterious light emitting when the planet was revolving around the star. They studied the star light alone and found that when the planet disappears from view, the light from the star system dips ever so slightly, but enough that astronomers can determine how much light came from the planet itself. This information reveals the temperature of a planet, and, in some cases, its atmospheric components.
The 55 Cancri e planet is a super earth, but this super earth is more massive than our home world but lighter than giant planets like Neptune. It is about twice as big and eight times as massive as earth. This planet orbits a bright star, called 55 Cancri. It just takes 18 hours to orbit its star, whereas planet earth takes 365 days to orbit our sun.
The star, 55 Cancri has five planets, among which 55 Cancri e is the closest to the star. Planet 55 Cancri e is tidally lockedwhich means that only one side of the planet always faces the star. Spitzer discovered the sun-facing side is extremely hot, indicating the planet probably does not have a substantial atmosphere to carry the sun's heat to the unlit side.
Earlier, astronomers using Spitzer and other telescopes had studied the planet by analysing how the light from 55 Cancri changed as the planet passed in front of the star. In the new study, Spitzer measured how much infrared light comes from the planet itself. The results reveal the planet is likely dark and its sun-facing side is more than 2,000 Kelvin (3,140 degrees Fahrenheit), hot enough to melt metal.
The new information is consistent with a prior theory that 55 Cancri e is a water world: a rocky core surrounded by a layer of water in a "supercritical" state where it is both liquid and gas, and topped by a blanket of steam.
"It could be very similar to Neptune, if you pulled Neptune in toward our sun and watched its atmosphere boil away," said Michaël Gillon, scientist at the Université de Liège in Belgium, in a statement.
"Spitzer has amazed us yet again," said Bill Danchi, Spitzer programme scientist at Nasa headquarters in Washington, in a statement. "The spacecraft is pioneering the study of atmospheres of distant planets and paving the way for Nasa's upcoming James Webb Space Telescope to apply a similar technique on potentially habitable planets."
"When we conceived of Spitzer more than 40 years ago, exoplanets hadn't even been discovered," said Michael Werner, scientist at Nasa's Jet Propulsion Laboratory (JPL), in a statement. "Because Spitzer was built very well, it's been able to adapt to this new field and make historic advances such as this."
Watch the video