Astronomers have discovered water vapour and carbon monoxide in the atmosphere of an alien planet 130 light years away from Earth.

The star, known as HR 8799, is devoid of methane, a gas that can indicate life. It is at the centre of the first planetary system outside our solar system to be imaged directly, in 2008.

Nearly a thousand exoplanets are known currently, and NASA’s Kepler mission alone has discovered almost three thousand exoplanet candidates. However, HR 8799 and its planets are one of only a handful of systems beyond our own solar system that were seen directly.

"It's the only system in which multiple planets can individually be seen," said study co-author Bruce Macintosh, an astronomer at Lawrence Livermore National Laboratory in California.

Scientists think that this will not assist to solve mysteries of how it was formed and also how our own solar system came to existence. The planets orbiting HR 8799 weigh in at between five to 10 times the mass of Jupiter and are still glowing with the heat of their formation. Also, the light from the HR 8799c can be distinguished from its star, partially due to its distant orbit.

Quinn Konopacky from the Dunlap Institute for Astronomy and Astrophysics at the University of Toronto, along with colleagues from Canada and the United States, used data from the Keck Observatory in Hawaii to analyze the spectral features of HR 8799c. They analysed that to get the chemical composition of the distant planet’s atmosphere. The data came from 5.5 hours of observations, made up of 33 ten minute exposures. One of the Keck telescopes were used in Hawaii to get the most detailed look at its light yet.

"We have broken the light from the planet down to such a fine level of detail that the chemical fingerprints of the molecules in the atmosphere are breathtakingly sharp and distinct. This is important because it requires data of this quality to truly probe the makeup of a planetary atmosphere, and in turn, say something about how the planet formed," said Quinn Konopacky.

"Our results are most consistent with the planets around HR8799 forming via core accretion, much in the same way we think the planets in our own Solar System formed," explained Konopacky. "By studying the HR8799 system, we can get a peek at how Jupiter-like planets look very shortly after they form.".

The planetary system is young, with an approximate age of 30 million years. HR 8799c could be as hot as 1000C, and its gravity approximately 10 times that of Earth.

The observations, made using at the Keck Observatory in Hawaii, were published online in the journal Science.