Starship Asterisk*

[img3="An artistic rendering of an alien world crowded with volcanic activity. The hydrogen from volcanoes can help scientists possibly detect life on exoplanets.
Credit: W. G. Henning/NASA"]https://www.news.cornell.edu/sites/chro ... k=FI4Z-3ud[/img3][hr][/hr]

Hunting for habitable exoplanets now may be easier: Cornell University astronomers report that hydrogen pouring from volcanic sources on planets throughout the universe could improve the chances of locating life in the cosmos.

Planets located great distances from stars freeze over. “On frozen planets, any potential life would be buried under layers of ice, which would make it really hard to spot with telescopes,” said lead author Ramses Ramirez, research associate at Cornell’s Carl Sagan Institute. “But if the surface is warm enough – thanks to volcanic hydrogen and atmospheric warming – you could have life on the surface, generating a slew of detectable signatures.”

Combining the greenhouse warming effect from hydrogen, water and carbon dioxide on planets sprinkled throughout the cosmos, distant stars could expand their habitable zones by 30 to 60 percent, according to this new research. “Where we thought you would only find icy wastelands, planets can be nice and warm – as long as volcanoes are in view,” said Lisa Kaltenegger, Cornell professor of astronomy and director of the Carl Sagan Institute. ...

• Astrophysical Journal Letters 837(1):L4 (2017 Mar 01) DOI: 10.3847/2041-8213/aa60c8 (preprint)