Astronomers discover diamond-studded planet

London, Dec 9 (ANI): A team of astronomers, led by an Indian-origin boffin, has discovered the first carbon-rich planet, orbiting a star 1,200 light-years away, which could have an interior abundant in diamonds.

Unlike Earth, which is rich in oxygen and has much smaller quantities of carbon, the planet WASP-12b is dominated by carbon and depleted in oxygen.

The finding points to the existence of planets with compositions very different from those of our own Solar System.

The planet was originally found last year by the Wide-Angle Search for Planets (WASP) project, the UK's leading team of planet discoverers, using the WASP telescope in La Palma funded by the Science and Technology Facilities Council.

Now Nikku Madhusudhan and colleagues of the Massachusetts Institute of Technology have further observed WASP-12b with NASA's Spitzer Space Telescope and found that its atmosphere is dominated by molecules containing carbon.

"This is new territory and will motivate researchers to study what carbon-rich planets are made of", said Madhusudhan. "Although WASP-12b is a hot, Jupiter-sized 'gas giant' planet that would not have a surface, smaller rock planets could also form in such planetary systems".

"A rocky planet in such a planetary system could have an interior abundant in diamonds and a surface littered with graphite and diamonds", said Professor Joe Harrington, of the University of Central Florida, who led the analysis of the Spitzer data.

"The theorists will have fund with this one. Could life thrive in such an environment, with little oxygen or water? That might not be so far-fetched givenlast week's announcement by NASA of bacteria that can survive by using arsenic in place of phosphorus, previously thought to be essential".

"WASP-12b is one of our most important finds", says Prof. Don Pollacco, of Queen's University Belfast, who led the construction of the WASP camera array that found the planet. "It is the size of Jupiter and among the hottest planets known, orbiting its star in only 26 hours".

Because WASP-12b is so close to its star and so hot, the Spitzer Space Telescope can detect the heat of the planet, and studying this radiation tells us which molecules are in its atmosphere.

Earth is typical of Solar-System planets in having more oxygen than carbon. The Earth is mainly iron, oxygen and silicon, with silica-sand-being the commonest mineral. WASP-12b is the first planet found where the oxygen/carbon ratio is reversed. The oxygen/carbon ratio of WASP-12b was deduced by analyzing its infrared spectrum withSpitzer, and comparing the absorption features caused by carbon-rich molecules such as methane with those caused by water.

"The UK's WASP project, funded by the STFC, is finding many planets that are prime targets for NASA's Spitzer Space Telescope", explains WASP team member Dr. Pete Wheatley from the University of Warwick, who proposed that Spitzer observe WASP-12b. "It's fascinating to find a planet with so much carbon, and to imagine what other sorts of planet are out there".

The study has been reported in Nature this week. (ANI)