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NASA's Spitzer Space Telescope has detected light emanating from a"super-Earth" planet beyond our solar system for the first time.While the planet is not habitable, the detection is a historic steptoward the eventual search for signs of life on other planets. "Spitzer has amazed us yet again," said Bill Danchi, Spitzerprogram scientist at NASA Headquarters in Washington. "Thespacecraft is pioneering the study of atmospheres of distantplanets and paving the way for NASA's upcoming James Webb SpaceTelescope to apply a similar technique on potentially habitableplanets." The planet, called 55 Cancri e, falls into a class of planetstermed super Earths, which are more massive than our home world butlighter than giant planets like Neptune. The planet is about twiceas big and eight times as massive as Earth. It orbits a brightstar, called 55 Cancri, in a mere 18 hours. Previously, Spitzer and other telescopes were able to study theplanet by analyzing how the light from 55 Cancri changed as theplanet passed in front of the star. In the new study, Spitzer measured how much infrared light comesfrom the planet itself. The results reveal the planet is likelydark, and its sun-facing side is more than 2,000 Kelvin (3,140degrees Fahrenheit), hot enough to melt metal. The new information is consistent with a prior theory that 55Cancri e is a water world: a rocky core surrounded by a layer ofwater 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 intoward our sun and watched its atmosphere boil away," said MichaelGillon of Universite de Liege in Belgium, principal investigator ofthe research, which appears in the Astrophysical Journal. The leadauthor is Brice-Olivier Demory of the Massachusetts Institute ofTechnology in Cambridge. The 55 Cancri system is relatively close to Earth, at 41light-years away. It has five planets, with 55 Cancri e the closestto the star and tidally locked, so one side always faces the star.Spitzer discovered the sun-facing side is extremely hot, indicatingthe planet probably does not have a substantial atmosphere to carrythe sun's heat to the unlit side. NASA's James Webb Space Telescope, scheduled to launch in 2018,likely will be able to learn even more about the planet'scomposition. The telescope might be able to use a similar infraredmethod to Spitzer to search other potentially habitable planets forsigns of molecules possibly related to life. "When we conceived of Spitzer more than 40 years ago, exoplanetshadn't even been discovered," said Michael Werner, Spitzer projectscientist at NASA's Jet Propulsion Laboratory in Pasadena, Calif."Because Spitzer was built very well, it's been able to adapt tothis new field and make historic advances such as this." In 2005, Spitzer became the first telescope to detect light from aplanet beyond our solar system. To the surprise of many, theobservatory saw the infrared light of a "hot Jupiter," a gaseousplanet much larger than the solid 55 Cancri e. Since then, other telescopes, including NASA's Hubble and Keplerspace telescopes, have performed similar feats with gas giantsusing the same method. In this method, a telescope gazes at a star as a planet circlesbehind it. When the planet disappears from view, the light from thestar system dips ever so slightly, but enough that astronomers candetermine how much light came from the planet itself. This information reveals the temperature of a planet, and, in somecases, its atmospheric components. Most other currentplanet-hunting methods obtain indirect measurements of a planet byobserving its effects on the star. During Spitzer's ongoing extended mission, steps were taken toenhance its unique ability to see exoplanets, including 55 Cancrie. Those steps, which included changing the cycling of a heater andusing an instrument in a new way, led to improvements in howprecisely the telescope points at targets. We are high quality suppliers, our products such as Ceramic Guide Eyelet Manufacturer , China Yokogawa Tension Meter for oversee buyer. To know more, please visits Electronic Wire Tensioner.
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