SoylentNews

takyon writes:

Hubble finds compelling evidence for a moon outside the Solar System

Using the NASA/ESA Hubble Space Telescope and older data from the Kepler Space Telescope two astronomers have found the first compelling evidence for a moon outside our own Solar System. The data indicate an exomoon the size of Neptune, in a stellar system 8000 light-years from Earth. The new results are presented in the journal Science Advances.

[...] In 2017 NASA's Kepler Space Telescope detected hints of an exomoon orbiting the planet Kepler-1625b. Now, two scientists from Columbia University in New York (USA) have used the incomparable capabilities of the NASA/ESA Hubble Space Telescope to study the star Kepler-1625, 8000 light-years away, and its planet in more detail. The new observations made with Hubble show compelling evidence for a large exomoon orbiting the only known planet of Kepler-1625. If confirmed, this would be the first discovery of a moon outside our Solar System.

The candidate moon, with the designation Kepler-1625b-i, is unusual because of its large size; it is comparable in diameter to the planet Neptune. Such gargantuan moons are unknown in our own Solar System.

Other sources put Kepler-1625 at around 4,000 light years away.

Discoveries like this are why we could use as many identical better-than-Hubble space telescopes as we can build and launch.

Also at Sky & Telescope, Cosmos Magazine, The Verge, Axios, NPR, CNN.

Evidence for a large exomoon orbiting Kepler-1625b (open, DOI: 10.1126/sciadv.aav1784) (DX)

Previously: First Exo-Moon Discovered?
First Known Exomoon May Have Been Detected: Kepler 1625b i

Original Submission