Carbon dioxide found on extrasolar planet could lead to proof of extraterrestrial life



NASA's Hubble space telescope has discovered carbon dioxide in the atmosphere of a distant planet outside our solar system, a breakthrough which could be an important step toward finding evidence of extraterrestrial life.



The space agency said the Hubble found the CO2 in the atmosphere of 'hot Jupiter' planet HD 189733b, which orbits a nearby star 63 light-years from Earth.

Previous observations of HD 189733b's atmosphere by Hubble and the Spitzer Space Telescope found water vapour and methane.

Breakthrough: NASA's Hubble space telescope has discovered carbon dioxide in the atmosphere of a distant planet outside our solar system

Mark Swain of NASA's Jet Propulsion Laboratory in Pasadena, California used Hubble's near-infrared camera and multi-object spectrometer to study infrared light from the planet.

He was able to identify carbon dioxide and carbon monoxide, which absorb certain wavelengths of near-infrared radiation.

The extrasolar planet is itself too hot to support life - its surface is about 1,800°F (1,000°C) - but astronomers said they hope their observations could lead to the first evidence of life beyond our planet.

'The carbon dioxide is the main reason for the excitement because, under the right circumstances, it could have a connection to biological activity as it does on Earth,' Swain said.

Excitement: An artist's impression of the 'hot Jupiter' planet HD 189733b. The extrasolar planet orbits a nearby star 63 light-years from Earth

'The very fact we are able to detect it (CO2) and estimate its abundance is significant for the long-term effort of characterizing planets to find out what they are made of and if they could be a possible host for life.'

Eric Smith, Hubble Space Telescope program scientist at NASA, added: 'These atmospheric studies will begin to determine the compositions and chemical processes operating on distant worlds orbiting other stars.

'Hubble was conceived primarily for observations of the distant universe, yet it is opening a new era of astrophysics and comparative planetary science.

'The future for this newly opened frontier of science is extremely promising as we expect to discover many more molecules in exoplanet atmospheres.'