Milky Way, signs of life and water: See what this studies found
A third of the planets orbiting the Milky Way’s most common stars may contain liquid water and harbor life, according to a new study based on the latest telescope data. Most of the common stars in our galaxy are relatively smaller and cooler. Their mass is at most half that of the Sun. Billions of planets orbit these ordinary dwarf stars.
Two-thirds of the planets around these small, ubiquitous stars could be exposed to extreme tides, sterilizing them, explains the analysis published in the Proceedings of the National Academy of Sciences.
“I think this result is really important for exoplanet research in the next decade, because all eyes are on this group of stars,” said Sheila Sager, a PhD student at the University of Florida (UF) in the US. He added: “These stars are excellent targets to look for small planets in orbits where it is possible that water could be liquid and therefore the planet could be habitable.”
“Only the habitable zone of these young stars is close enough for tidal forces to be relevant,” says UF astronomy professor Sarah Ballard.
The researchers used data from NASA’s Kepler telescope. The agency said it collects information about exoplanets as they move in front of their host stars.
The research team found that stars with multiple planets are more likely to have circular orbits that allow liquid water to be stored.
According to the researchers, stars with only one planet were most likely to see extreme tides that would sterilize the surface. They explained: “Since a third of the planets in this small sample have orbits gentle enough to host liquid water, this likely means that the Milky Way has hundreds of millions of promising targets to search for signs of life outside our solar system.”
