The James Webb Space Telescope (JWST), launched to explore the cosmos in unprecedented detail, has not yet discovered an exomoon—moon-like bodies orbiting planets outside our solar system—despite expectations that it might. A new preprint paper by David Kipping, an astronomer at Columbia University, suggests that JWST can detect exomoons by observing the same location repeatedly. Kipping used data from 12 transits of the exoplanet LP 890-9 c, which orbits an ultracool red dwarf star about 105 light-years from Earth. This planet has an orbital period of 8.46 days and is located in the habitable zone of its star, where conditions might allow for liquid water. One of the challenges in detecting exomoons is "red noise," which refers to slow fluctuations in the telescope's instruments or variations in the star’s surface, such as sunspots. These can mask the subtle signals of small exomoons. By averaging data from multiple transits, Kipping showed that these disturbances can be minimized, improving the telescope's ability to detect exomoons. In one of the 12 transits, noticeable red noise was present, but when combined with data from a single "clean" transit, the sensitivity improved significantly. Despite this improved sensitivity, the study found no evidence of moons larger than 0.1 Earth radii orbiting LP 890-9 c, with 95% confidence. This means there are no moons similar in size to Jupiter’s moon Io or Saturn’s moon Enceladus around the exoplanet. However, the study confirms that JWST can detect moons as small as Earth’s moon, provided astronomers observe multiple transits. LP 890-9 c orbits very close to its star, at just 0.04 astronomical units—less than a tenth of the distance between the sun and Mercury. The intense gravitational forces from the star are expected to either strip a moon away or pull it inward, making it unlikely for a moon to remain stable. Kipping used this exoplanet as a test case to demonstrate the feasibility of detecting exomoons, not necessarily to find the first one. The study highlights that while JWST is capable of detecting exomoons, the main challenge is securing enough observation time. Telescope time is a limited and highly valuable resource, and the research suggests that finding an exomoon may be possible with more dedicated observations in the future.