The first ever unsettled detection of a exomoon outside our Solar System has been called into question. Astronomers are detecting the presence of a planet’s moon which would be a big deal.
Two teams performed independent analyses. One found that the exomoon detection signal was likely a blip in the original data. The other found a similar solution to the initial analysis, but cautioned that it was not a conclusive detection of an exomoon.
Astronomers suppose there must be a lot of them out there after all, the Solar System has way more moons than it does planets, so theoretically they should be pretty common.
When trying to detect exomoons, however, there are two big problems.
- The first is that exomoons would be much smaller than the exoplanets they orbit, meaning any effects we can observe would also be much smaller.
- The second issue is that astronomers need to be able to separate any supposed exomoon effects from the effects of its host planet.
According to the pair’s calculations, the exomoon was about the size of Neptune, which would make it also a gas giant the first gas giant moon ever seen, raising interesting questions about moon formation.
There remains one more piece of evidence still pointing to the possible existence of an exomoons. In the data, the planet started its transit 1.75 hours earlier than expected consistent with something gravitationally tugging on it. Like, say, a huge moon.