The existence of alien life has been a debatable topic for a very long time. For centuries, scientists and researchers have conducted various studies to understand conditions that would sustain extraterrestrial life in order to narrow down the search in the universe of innumerable planets and exoplanets and millions of galaxies.

According to the Independent, a "pioneering new study" unravels which planets could possibly host alien life and which may not.

"Now scientists are working out what planets we should be looking at," said Howard Chen, the author of the study.

Scientists at Northwestern University, University of Colorado Boulder, NASA's Virtual Planet Laboratory and the Massachusetts Institute of Technology have "redefined our understanding of whether the planet could be habitable" or not. For the study, the researchers studied "radiation coming from a star" and "how the planets rotate."

Published in Astrophysical Journal, the study found out how the radiation from a nearby star can influence the temperature of the atmosphere of a rocky planet. That, in turn, can help in figuring out whether water, a necessary component for life to grow there, exists on the planet. More findings indicate that planets around active stars may not be suitable for life sustainability as they lose their water into vapour. Meanwhile, worlds with "quiet" stars are more likely to be "home for alien life."

The extensive study goes on to reveal that planets with thin ozone layers may not be habitable, rather dangerous for any kind of complex life.

"Still, there are a lot of stars and planets out there, which means there are a lot of targets," Daniel Horton, a senior author of the study said. "Our study can help limit the number of places we have to point our telescopes," he added.

Alien life search
METI planning to contact alien life in 2018 REUTERS/NASA/Handout via

Scientists have spent a very long time to find proof of alien life without a certain answer. However, this study attempts to streamline the research and where in the vast universe they are looking at.