NASA says some Icy Exoplanets could be habitable for humans
A NASA study expands the search for life beyond our solar system by indicating that 17 exoplanets (worlds outside our solar system) could have oceans of liquid water, an essential ingredient for life, beneath icy shells. Water from these oceans could occasionally erupt through the ice crust as geysers. The science team calculated the amount of geyser activity on these exoplanets, the first time these estimates have been made. They identified two exoplanets sufficiently close where signs of these eruptions could be observed with telescopes.
The search for life elsewhere in the Universe typically focuses on exoplanets that are in a star’s “habitable zone,” a distance where temperatures allow liquid water to persist on their surfaces. However, it’s possible for an exoplanet that’s too distant and cold to still have an ocean underneath an ice crust if it has enough internal heating. Such is the case in our solar system where Europa, a moon of Jupiter, and Enceladus, a moon of Saturn, have subsurface oceans because they are heated by tides from the gravitational pull of the host planet and neighboring moons.