Home » News & Blogs » Deep Alien Biospheres
Bookmark and Share
Beyond Earthly Skies

Deep Alien Biospheres

23 Nov 2013, 09:40 UTC
Deep Alien Biospheres
(200 words excerpt, click title or image to see full post)

Life on Earth not only exists on the surface, but it also includes a subsurface biosphere extending several kilometres in depth. At such depths, the only reasonable source of energy to sustain life comes from the planet's own internal heat. Indeed, a planet that is located far from its host star, resulting in surface temperatures too cold to support life, can potentially harbour a thriving subsurface biosphere that is sustained solely by the planet's own internal heat.Figure 1: Artist’s impression of a terrestrial planet. Figure 2: Artist’s impression of a terrestrial planet. Credit: Kevin Sherman.A study by S. McMahon et al (2013) show that subsurface liquid water maintained by the internal heat of a planet can support an underground biosphere even if the planet is too far from its host star to support life on the planet's surface. The authors introduce a term known as the “subsurface-habitability zone” (SSHZ) to denote the range of distances from a star where a terrestrial planet (i.e. a rocky planet like the Earth) can sustain a subsurface biosphere at any depth below the surface down to a certain maximum habitable depth. This maximum depth depends on numerous factors, but in general, it is the ...

Latest Vodcast

Latest Podcast

Advertise PTTU

NASA Picture of the Day

Astronomy Picture of the Day

astronomy_pod