WEBVTT FILE 1 00:00:00.000 --> 00:00:03.670 Scientists using NASA's Hubble Space Telescope 2 00:00:03.670 --> 00:00:07.274 just found intriguing evidence of the first possible exomoon. 3 00:00:07.274 --> 00:00:14.147 Exomoons are moons orbiting planets outside our solar system. 4 00:00:14.147 --> 00:00:16.283 The Kepler spacecraft showed the first hints 5 00:00:16.283 --> 00:00:20.988 of a moon orbiting exoplanet Kepler-1625b. 6 00:00:20.988 --> 00:00:25.092 Now Hubble has also observed a transit of the planet 7 00:00:25.092 --> 00:00:27.961 with a signature that appears to be a moon. 8 00:00:27.961 --> 00:00:35.035 [music] 9 00:00:35.035 --> 00:00:38.372 If truly a moon, it would be the size of Neptune 10 00:00:38.372 --> 00:00:41.875 and its planet is bigger than Jupiter. 11 00:00:41.875 --> 00:00:49.049 More Hubble observations will confirm what this truly is. 12 00:00:49.049 --> 00:00:52.619 Learn more at... 13 00:00:52.619 --> 00:00:00.000 www.nasa.gov/hubble @NASAHubble