habitable exoplanet tagged posts

Astrophysicists studying a popular exoplanet in its star’s habitable zone have found that electric currents in the planet’s upper atmosphere could create sufficient heating to expand the atmosphere enough that it leaves the planet, likely leaving the planet uninhabitable.

Until now, planetary scientists have thought that a habitable planet needs a strong magnetic field surrounding it to act as a shield, directing ionized particles, X-rays and ultraviolet radiation in the stellar wind around and away from its atmosphere.
That’s what happens on Earth, preventing dangerous radiation from reaching life on the surface, and what does not occur on Mars, which now lacks a global magnetic field, meaning any initial inhabitants of the red planet will probably need to live in underground caves...

An artist’s conception of Kepler-62f, a planet in the ‘habitable zone’ of a star located about 1,200 light-years from Earth. Credit: NASA Ames/JPL-Caltech/T. Pyle

Combined climate, orbit models show Kepler-62f might be able to sustain life. The planet, in the direction of constellation Lyra, is ~40% larger than Earth. At that size, Kepler-62f is within the range of planets that are likely to be rocky and possibly could have oceans. NASA’s Kepler mission discovered the planetary system that includes Kepler-62f in 2013, and it identified Kepler-62f, the outermost of 5 planets orbiting a star that is smaller and cooler than the sun. but there was no composition, atmosphere or orbit data.

To determine whether the planet could sustain life, the team came up with possible scenarios about what it...