Scientists May Have Found The First Moon Outside The Solar System

Space

Advertisment

By Jonathan O'Callaghan

28/07/2017, 15:02

In what would be a pretty major discovery, astronomers say they may have found the first moon beyond the Solar System – known as an exomoon.
The potential discovery is 4,000 light-years away around a star called Kepler-1625. It was made using NASA’s Kepler Space Telescope by three astronomers, Alex Teachey and David Kipping from Columbia University, and a citizen scientist called Allan Schmitt.
They published their results in a paper available on arXiv, and submitted to journals for review.
If it turns out to be real, the exomoon is thought to be about the mass of Neptune and orbits a planet that’s about 10 times the mass of Jupiter but the same size.
The signal observed by the astronomers was a double dip in the star’s light as the planet, and then the moon, passed in front relative to us – known as the transit method.
The astronomers have said they’re confident it’s a moon to a level of about 4.1 sigma. This means if the moon is not real, there’s about a one in 16,000 chance of seeing such a signal again, as New Scientist points out.
While it looks pretty good at the moment, we can’t say for certain. Currently, the signal is merely consistent with what we’d expect to see from a moon, but it could be something else. Now, they’ll use the Hubble Space Telescope in October to try and confirm the finding.
“Until we get the measurements from Hubble, it may as well be 50-50 in my mind," Kipping told BBC News.