It seems to be confirmed the existence of the first exomoon ever detected: a gaseous satellite that revolves around a gaseous planet, Kepler 1625b, 8,000 light years from us. Thanks to the Hubble Space Telescope, two researchers from Columbia University have found important confirmations on the existence of the first ever unidentified, which revolves around Kepler 1625b.
Alex Teachey and David Kipping report that the satellite (of which they had already hypothesized existence long ago) is particularly unusual because of its large size: it would have a diameter comparable to that of the planet Neptune (over 49,000 km). In the Solar System there are a total of about 200 natural satellites, but none of these dimensions. During their “hunting for exomoons”, the two researchers observed and analyzed data from about 300 planets with relatively large orbits, with periods of revolution around their star long over 30 days.
This particular kind of study is the obscuring of the light of a star when one of its planets passes in front of it, the observations showed anomalies in the transit of the planet Kepler 1625b in front of its star (Kepler-1625). Anomalies that have proved sufficient to allow the two researchers to use the Hubble telescope to study the planet more in depth.
Hubble measured a second fluctuation of light, smaller than that caused by the planet, which lasted three and a half hours: the measurements would be in agreement with a moon that is being dragged from its planet. Apart from this Hubble provided further evidence to support the existence of the satellite, in fact, it detected the beginning of the transit an hour and 25 minutes earlier than expected. This fact is consistent with the existence of a planet and a moon orbiting a common center of gravity. All those who look in our direction, would see similar anomalies, generated precisely by the transit of the Earth-Moon system in front of the Sun.
Kepler 1625b and its moon are located within the habitable zone of their parent star, where moderate temperatures would allow the presence of liquid water on any solid planetary surface. Unfortunately, however, both planets are gaseous and therefore unfit for life as we know it.
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