A team of astronomers has been analyzing the images captured by the Kepler spacecraft, and reached an interesting conclusion. They think they have spotted an image of the first exomoon ever discovered. This is a moon the size of Neptune outside of our solar system, orbiting a planet the size of Jupiter. Now, researchers will continue their studies, to establish if the cosmic object is indeed what they think it is.
What have astronomers discovered?
The potential exomoon is way bigger than the moons present in our solar system, as it is almost the size of Neptune. In fact, it is orbiting the big exoplanet Kepler-1625b, which is as big as Jupiter. Astronomers chose both an official name and a nickname for the candidate. The official name is Kepler-1625b I, but they often call it the Nep-moon.
Scientists can discover new cosmic objects by studying the images captured by the Kepler spacecraft. They observe the light cast by a faraway star, and monitor each time when it dims. This means that other cosmic objects pass in front of them. In our case, the star system is about 4,000 light-years away, so our exomoon could be any cosmic object.
Is the object really an exomoon?
In 2014, there was another candidate for the exomoon title, but astronomers managed to detect it only through microlensing. This means they couldn’t verify their hypothesis. However, microlensing occurs quite rarely, and Nep-moon was detected through a different phenomenon, occurring more often.
Therefore, the research team has already decided to take a better look at this object in October 2017, using the Hubble Space Telescope. Until they finish all observations and have all results, they cannot confirm Nep-moon is actually an exomoon.
Other scientists agree with this way of thinking. Although many signs indicate that the object is an exomoon, all proof is needed before establishing its membership to this category.
Image Source: Wikimedia Commons