A new study of NASA data claims to have found the most accurate estimate of Earth-like planets orbiting Sun-like stars. These exoplanets are similar in size to Earth and circle their respective stars from a similar distance – about 93 million miles (149.6 million km). Earth is one of the very few lucky planets that has found itself in the so-called Goldilocks Zone where conditions are just right for liquid water to exist. If NASA can narrow down the number of alien worlds that exist in similar orbits, the space agency will have a better chance of finding habitable planets.
Since 2009, NASA’s Kepler Space Telescope has found thousands of planet candidates peppered throughout the cosmos.
A paper published in The Astronomical Journal on August 14 has now investigated how these discoveries can help search for alien life.
Eric Ford, a professor of astronomy at Penn State University, said: “Kepler discovered planets with a wide variety of sizes, compositions and orbits.
“We want to use those discoveries to improve our understanding of planet formation and to plan future missions to search for planets that might be habitable.
NASA news: The Kepler telescope hunted down habitable exoplanets (Image: NASA/AMES/W.STENZEL/D.RUTTER)
NASA news: The Kepler telescope mission in numbers (Image: NASA)
“However, simply cutting exoplanets of a given size or orbital distance is misleading, since it’s much harder to find small planets far from their star than to find large planets close to their star.”
We want to use those discoveries to improve our understanding of planet formation
Eric Ford, Penn State University
NASA’s retired Kepler telescope observed a portion of the Milky Way galaxy to determine how many stars could be hosts to habitable planets.
The space probe scanned bright stars for brief dips in brightness caused by transiting planets.
During its nine-and-a-half year tenure, the NASA instrument has discovered more than 2,600 planets orbiting more than 530,000 stars.
Danley Hsu, a graduate student at Penn State, said: “We used the final catalogue of planets identified by Kepler and improved star properties from the European Space Agency’s Gaia spacecraft to build our simulations.
“By comparing the results to the planets catalogued by Kepler, we characterised the rate of planets per star and how that depends on planet size and orbital distance.
“Our novel approach allowed the team to account for several effects that have not been included in previous studies.”
The researchers have f