Evidence of possible exomoon detected for the first time

Researchers have found evidence of what may be a moon outside of our solar system. Assuming they have discovered an exomoon, it will be the first of its kind ever found, marking a new milestone in the exploration of the universe around us. The possible exomoon is located in the Cygnus constellation about 8,000 light-years from Earth.

The evidence was found by Columbia University astronomers Alex Teachey and David Kipping while analyzing info from 284 planets discovered by Kepler. These planets have "comparatively wide orbits," according to NASA, which last longer than 30 days. Of the data, one planet — Kepler-1625b — presented a transit signature that had "intriguing anomalies" that researchers believe may point toward an exomoon.

Finding moons outside of our solar system is tricky compared to finding exoplanets. The discovery of both depends on detecting transits, which is the temporary dimming of a star when the planet — or moon — passes in front of it. Moons, due to their smaller size and shifting position, are harder to detect.

According to NASA, the team was able to observe the planet using the Hubble telescope, monitoring it for dips in light during its 19-hour transit. Following 3.5 hours after that transit, the telescope also picked up a second decrease in star brightness described as "much smaller" than the first.

That second dip in light may have resulted from a moon trailing the larger planet, which is orbiting the host star. Researchers aren't positive at this time that they've found an exomoon — the Hubble observations were scheduled for a set amount of time, which ended before the second transit was complete.

SOURCE: NASA