Warming effect due to greenhouse is not at all bad. It has its own productive use not on our planet but on exoplanets that tend to freeze over.

The search for alien life is more likely to be easier than before, thanks to hydrogen of volcanic origin.

"On frozen planets, any potential life would be buried under layers of ice, which would make it really hard to spot with telescopes," Ramses Ramirez, lead author of the research published in The Astrophysical Journal Letters on Feb. 27, said.

Warming Effect

Exoplanets with warm surface could make the search to find signs of life easier. The combination of volcanic hydrogen and atmospheric warming can do just that.

It is known that planets can be warmed up by hydrogen, but it will last only for only several million years on exoplanets orbiting a great distance around the parent star. With volcanoes, however, it is now possible for a star to expand its habitable zone by 30 to 60 percent.

The effect of volcanic hydrogen on the planet will last long enough to support detectable life on its surface, Ramirez said.

Pouring a combination of hydrogen, water, and carbon dioxide to create a greenhouse warming on exoplanets increases the chances for astronomers to find alien life from a telescope.

It enhances the signal, "making it easier to spot the makeup of the atmosphere," Ramirez said.

Discarded Exoplanets Back Into Contention

The habitable zone in the solar system reaches beyond the orbit of Mars — about 1.67 times the Earth-sun distance — which could be extended further between Mars and Jupiter with the outpouring of volcanic hydrogen.

Many exoplanets considered too cold to sustain life prior to this research are now back into contention. The list of exoplanets capable of supporting life may grow tremendously, the researchers claimed, as long as there is a detectable hydrogen gas on them.

Hydrogen, a very light gas, also enhances atmospheres of planets — considered a big help in the search for more exoplanets that have potential to support life.

As long as there are volcanoes in the icy alien wastelands, "planets can be nice and warm," Lisa Kaltenegger, professor of astronomy and director of Carl Sagan Institute, said.

Signs of life in the atmosphere, which include the combination of methane and ozone, will be even more detectable by the powerful James Webb Space Telescope set to be launched next year.