Combining Models for the First Time
The Kepler Mission, which has been uncovering literally thousands of new planets since it started gazing out into the cosmos in 2009, discovered the exoplanet Kepler 62f in 2013.
Kepler 62f is a rather remarkable planet. It is 1200 light-years away. We know that it orbits a star that is smaller and cooler than the Sun, and is the outermost of the five planets in the system. And it’s just 40% larger than the Earth (most planets that we’ve found to date are enormous gas giants).
Moreover, the data from the Kepler telescope suggests that 62f is a rocky planet that might have oceans.
Now, simulations conducted by a team of scientists have revealed several scenarios that posit that 62f is likely to be habitable, adding it to the ever-growing list of candidates for extraterrestrial life (as well as the list for potential Earth 2.0s).
That Planetary Sweet Spot
By combining different modeling systems, astronomers are able to infer whether a planet has the potential to sustain life. This is known as the Community Climate System Model (CCSM), which in itself is comprised of four separate models that simultaneously simulate the Earth’s habitable atmosphere, the Laboratoire de Me´te´orologie Dynamique Generic model, and the computer model Hnbody.
Based on the luminosity of the host star, astronomers can determine the planetary sweet spot, referred to as the Goldilocks zone, where the temperature is neither too hot nor too cold and liquid water can exist, which is necessary for life as we know it.
Other factors for habitability then come into play, such as the size of the planet and its carbon dioxide concentration, atmospheric density, and orbital characteristics. And it seems that 62f fits the bill.
“We found there are multiple atmospheric compositions that allow it to be warm enough to have surface liquid water,” said Aomawa Shields, a University of California President’s Postdoctoral Program Fellow who leads the team. “This makes it a strong candidate for a habitable planet.”
While the Kepler telescope does not have the ability to distinguish the habitability of a planet, the multiple model scheme can help make intelligent guesses. “This will help us understand how likely certain planets are to be habitable over a wide range of factors, for which we don’t yet have data from telescopes. And it will allow us to generate a prioritized list of targets to follow up on more closely with the next generation of telescopes that can look for the atmospheric fingerprints of life on another world,” Shields says.