A moon outside our solar system! In a paper published Oct. 3 in the journal Science Advances, Alex Teachey and David Kipping report the detection of a candidate exomoon. This means moons orbiting planets in another star system which is unusual because of its large size, comparable to the diameter of Neptune. Such gargantuan moons do not exist in our own solar system, where nearly 200 natural satellites have been cataloged.
The first known moon beyond our solar system was discovered about 8,000 light years ago. It is gaseous and 15 times bigger than our moon. The finding may lead to theories on the formation of moons being revisited, David Kipping, of Columbia University in New York, said.
Finding moons are much frequent as they are common in our solar system; nearly 200 natural satellites, but the long search for interstellar moons has been an empty one. Astronomers have faced success locating exoplanets around stars outside our solar system, but exomoons are harder to identify because of their smaller size. They also shift position with each transit because the moon is orbiting the planet. In addition, the ideal candidate planets hosting moons are in large orbits, with long and infrequent transit times.
As informed, Dr. Kipping has spent a decade working on the “exomoon hunt.” The researcher analyzed data from 284 planets discovered by the Kepler telescope that launched in 2009 on a mission to discover Earth-size planets orbiting other stars. Kepler looks for the momentary diffusing of brightness caused by the transit of a planet and is often a snitch sign of a planet’s existence.
Future searches by NASA will target Jupiter-sized large planets that are farther from their star than Earth is from the Sun. There is just a handful of these as per the Kepler database. As Kipping said, “We can expect to see really tiny moons.”
The minds behind this discovery are hesitant to confirm that the new find is an exomoon due to some of its peculiarities and the fact that more observation is needed. However, the finding is both promising and intriguing as there’s no analog for such a large moon in our own system.