Sep 16, 2010 14:45 GMT  ·  By

Planetary scientists are currently puzzled at the fact that a hot exoplanet that was recently discovered appears to be mission the chemical methane from its atmosphere.

Researchers are at a loss in explaining why the gas giant, who is larger than Jupiter, fails to show traces of the hydrocarbon, which is extremely common in worlds of this class.

The four planets in our solar system that meet the gas giant classification, Jupiter, Saturn, Uranus and Neptune, all exhibit very high amounts of methane in their atmosphere.

In the case of the Saturnine moon Titan, the space body's poles are laden with lakes in which hydrocarbons such as methane and ethane form liquid lakes.

But investigations on the chemical composition of the atmosphere around extrasolar planet GJ 436b revealed very little traces of the chemical.

The investigations were conducted by a team of astronomers University of Central Florida, who used the American space agency's Spitzer Space Telescope for the job.

This particular observatory is especially well suited for the job because it can observe targets in the infrared portion of the electromagnetic spectrum, which means that it can reach places that remain invisible for telescope that work with visible light.

When the instrument was trained at GJ 436b, which is located fairly close at just 33 light-years away from Earth, it identified only minute amounts of methane in the atmosphere.

“Methane should be abundant on a planet of this temperature and size, but we found 7,000 times less methane than what the models predict,” explains UCF astronomer Kevin Stevenson.

He made the announcement in the new statement that NASA released on Monday. He was also the author of a study on the exoplanet, which was published this April.

What makes the mystery even deeper is the ease with which methane is produced. It is basically made up of four hydrogen atoms tied to a single carbon atom, and appears whereas the two chemicals are found.

What the team did discover on the peculiar exoplanet was that its atmosphere was laden with carbon monoxide. This “blew our minds,” adds UCF study coauthor Joseph Harrington, also the principal investigator of the research.

The leading explanation today is that the chemical abnormality is caused by ultraviolet radiation.

“If you put plastic wrap out in the sun, the UV radiation breaks down the carbon bonds in the plastic, causing it to deteriorate as the long carbon chains break,” Harrington explains.

“We propose a similar process on GJ 436b, but there hydrogen atoms split off from methane and let the remnants stick together to make ethylene,” he concludes, quoted by Space.