New Tool in the Hunt for Alien Life: Methane Detection on Exoplanets

Scientists hunting for alien life may have a new tool in their arsenal. Researchers have created a powerful new model to detect life on planets outside of our solar system more accurately than ever before.

The model itself focuses on methane, which is the simplest organic molecule and is widely acknowledged to be a sign of potential life. More specifically, the researchers have managed to develop a new spectrum for "hot" methane which can then be used to detect the molecule at temperatures above that of Earth.

The researchers used supercomputers to calculate nearly 10 billion spectroscopic lines, each with a different color at which methane can absorb light. In fact, the new list is about 2,000 times bigger than any previous study.

So how does this help detect life? Researchers analyze the way in which exoplanets' atmospheres absorb starlight of different colors in order to find out what the planets themselves are made out of. This allows them to identify different molecules in the planet's atmosphere. Without a model, though, the researchers have nothing to which to compare an exoplanet's ability to absorb starlight.

"Current models of methane are incomplete, leading to a severe underestimation of methane levels on planets," said Jonathan Tennyson, one of the researchers, in a news release. "We anticipate our new model will have a big impact on the future study of planets and 'cool' stars external to our solar system, potentially helping scientists identify signs of extraterrestrial life."

The findings are important for understanding the atmospheres of other planets. This, in turn, could help scientists track down life outside our solar system.

"The comprehensive spectrum we have created has only been possible with the astonishing power of modern supercomputers which are needed for the billions of lines required for the modeling," said Sergei Yurchenko, one of the researchers, in a news release. "We limited the temperature threshold to 1,500K to fit the capacity available, so more research could be done to expand the model to higher temperatures still. Our calculations required about 3 million CPU (central processing unit) hours alone; processing power only accessible to us through the DiRAC project."