Search for alien life more complicated than thought, scientists say

Oct. 8, 2013 at 6:10 PM   |   Comments

DENVER, Oct. 8 (UPI) -- Finding life on distant exoplanets may be more difficult than scientists thought, researchers from China, the United States and Argentina said Monday.

Recent observations of several planet-hosting M dwarf stars -- the focus of current efforts to find Earth-like planets -- showed ultraviolet properties of the small stars are quite different from those of the sun, which could further complicate the search for alien life, the researchers told a meeting of the American Astronomical Society Division for Planetary Sciences in Denver.

That could complicate the search for chemical signs of life, they said.

Feng Tian, a professor at Tsinghua University, and his U.S. and Argentine colleagues have shown that the atmosphere of a hypothetical habitable planet around such a star could build up significant levels of oxygen -- one possible "signature" of alien life -- even in the absence of any such life.

"Before we can claim the discovery of life on exoplanets, we have to examine the stars harboring these planets more carefully," the researchers said.

Other scientist agreed.

"The authors of this paper make an important point regarding the confidence we could have in the detection of O2 simultaneously with H2O and CO2, as a biosignature in the spectrum of an Earth- like exoplanet around an M star," Alain Leger of the Institute d'Astrophysique Spatiale at University of Paris said.

© 2013 United Press International, Inc. All Rights Reserved. Any reproduction, republication, redistribution and/or modification of any UPI content is expressly prohibited without UPI's prior written consent.
Most Popular
Male gators attracted to tuba's B flat
Worldwide water shortage by 2040, new studies suggest
Music helps cows relax, produce more milk
Thousands of velellas wash up on the shores of San Francisco
Harry Potter kills Voldemort, solves racism
Trending News