This potential new moon orbits a giant, Jupiter-sized planet about 8,000 light-years from Earth. The planet located outside our solar system is called exoplanet and its moon, that is, the satellite is called "exomoon".
In the Kepler exoplanet catalog, there are only a few Jupiter-size planets that are farther from their star than Earth is from the sun - good candidates for moons due to the distance.
However, given that both the planet and its potential moon are gas giants, no one is suggesting conditions that might support life.
Plenty of planets exist beyond our solar system, but a moon around one of those worlds has yet to be confirmed.
"If confirmed by follow-up Hubble observations, the finding could provide vital clues about the development of planetary systems and may cause experts to revisit theories of how moons form around planets", Kipping said.
Teachey and Kipping believe the moon is approximately the size of Neptune, making it larger than any moon in our solar system.
According to the recent study, the object orbiting Kepler-1625b might indeed be an exomoon as the giant planet passed before its host star one hour before the astronomers predicted. This occurs when the exoplanet passes in front of the star, and the method is therefore called the "transit method".
All of this makes sense if a huge Neptune-sized moon is orbiting Kepler 1625b.
Accepting that the data do indeed show evidence for an additional body co-orbiting the star with the planet Kepler-1425b, the question arises - is this really a moon?
The exomoon is exponentially larger than our solar system's biggest moon. Astronomers have had success locating exoplanets around stars outside our solar system, but exomoons are harder to pinpoint due to their smaller size. They watched the planet during its 19-hour transit.
In an attempt to confirm their original tentative detection, the team behind the new study scheduled high precision measurements of Kepler-1625 with the Hubble Space Telescope, which were carried out in October 2017. And finding future moons will require looking at planets much further out from their stars, something that is hard now, but should possible once the powerful but long-delayed James Webb Space Telescope finally begins scanning the skies.
"We saw little deviations and wobbles in the light curve that caught our attention", Dr.
They were hoping to find a moon that was the size of Jupiter's large moons, and then requested for a more detailed observation with the Hubble telescope. The ideal candidate planets hosting moons are in wide orbits, with long and infrequent transit times.
"Furthermore, the size we've calculated for this moon, about the size of Neptune, has hardly been anticipated and so that, too, is reason to be careful here". On the other hand, the scientists agreed that another planet in Kepler-1625b's vicinity might also cause such turbulence.
"When we run our model, the moon hypothesis was the best and only single explanation for the timing effects and the dimming of the star that we see in the data", Teachey said.