First exo-moon discovered? Astronomers present evidence

Astronomers have spotted an object in a distant planetary system that may be the first known moon orbiting an extrasolar planet. This moon is the size of Neptune and is located 8,000. light years away.

Moons in the Solar System are common. Earth has one, Mars has two, and Jupiter and Saturn have dozens each. Given the moon’s abundanceoin our planetary system, it is reasonable to assume that there are dozens of them outside the solar system as well. However, they have remained elusive until now, but all indications are that this has just changed.

Astronomers at Columbia University using the Hubble Space Telescope'a and the Kepler Space Telescope have collected convincing evidence of the existence of a moon orbiting wokoł gas giant located 8,000 light years from Earth.

In an article published in the journal „Science Advances”, Alex Teachey and David Kipping reported the detection of a candidate exoplanet, or moon orbiting wokoł planet in another planetary system.

The discovered object is unusual for its considerable size. It is the size of Neptune and orbits around theoł a planet the size of Jupiter, only several times more massive. Such large moons do not exist in our Solar System.

– This would be the first time a moon has been detected outside our solar system, said Kipping, a professor of astronomy at Columbia University. – If the discovery is confirmed by further observations, it could provide important cluesowks on the development of the systemoin planetary. Perhaps the roalso cause experts to reexamine theories of moon formationowokoł planets – added.

In search of an exoplanetow scientists have analyzed data from 284 planets discovered by the Kepler telescope, whichore were in relatively wide orbits, with orbital periods around aoł of its parent star longer than 30 days. While observing the exoplanet Kepler 1625b in transit against its parent star, they noticed intriguing anomalies.

– We saw slight deviations and fluctuations in its brightness curve, which theore attracted our attention – Kipping said.

Scientists using the telescopeoIn Hubble’a and Kepler monitored the planet before and during its 19-hour transit against the background of its star’s disk. Even after the transit was over, Hubble Telescope data’a noticed another, but much weaker decrease in the brightness of the star. Unfortunately, the scheduled observations ended before a complete transit of the moon could be measured, but observations nevertheless indicated the presence of the moon following the planet.

In addition, Hubble provided evidence that seemed to support the moon hypothesis, recording the transit of the planet more than an hour earlier than expected. This is consistent with the model, in whichorym moon and planet orbiting wokoł commonol common center of mass, which causes the planet to wobble periodically and change its predicted position minimally. – An extraterrestrial civilization observing the transit of the Earth and the Moon against the Sun would have noticed similar anomalies – explained Kipping.

Although the Kepler Space Telescope has not found any evidence ofow on the presence of additional planets in the observed system during its four-year mission, the researchers note that in principle such an anomaly could be caused by roAlso the gravitational pull of a hypothetical second planet.

– A planetary companion in the form of a moon is the simplest and most natural explanation for the second drop in the light curve and the deviation in orbit time, said Teachey, head of theown author of publications. – It was a shocking moment when I saw this data. My heart started beating a little faster – added.

Scientists have estimated that the moon has about 1.5 percent of the mass of the companion planet, whichora itself is several times more massive than Jupiter. This value is close to the mass ratio between the Earth and its Moon.

The planet Kepler 1625b and its moon are located in the so-called. eco-zone, where moderate temperatures may allow liquid water to exist on the planet’s surface. – However, both bodies are considered gas giants, so proIt is difficult to look there for signs of life, at least as we know it,” said Kipping.