An artist's concept illustrates a young, red dwarf star surrounded by three planets. ( NASA)
Looking for life beyond Earth? You now have twice as many planets to explore.
According to a study published in Astrophysical Journal Letters, there may be as many as 60 billion exoplanets in the so-called habitable zone around their stars - double what was previously thought.
Why the jump? Because a team of scientists from the University of Chicago and Northwestern University has created a 3-D model of how clouds would affect temperatures on alien worlds.
To be in a habitable zone, a planet needs to be just the right distance from its star so that liquid water (considered a requisite for life as we know it) can exist on the planet's surface.
If the planet is too near its star, the liquid water would turn to vapor; too far away, and the water would turn to ice.
For decades, scientists have determined whether a planet is in this liquid-water-friendly Goldilocks zone by calculating how far the planet is from its star, and how hot the star is burning.
But in the new study, astronomers at the University of Chicago show how cloud patterns can alter the temperature of a planet enough that planets that were previously considered too close to their stars to support liquid water might be able to support it after all.
