JWST search for exomoons around TOI 700 d and e sets new limits and refines planet properties

Star system: TOI 700 | Distance from the Sun: 102 light years

Scientists used the James Webb Space Telescope to search for exomoons, similar to Earth's Moon, around the rocky planets TOI 700 d and e, which orbit in the habitable zone of a red dwarf star. While no exomoons were detected, the study improved the precision of the planets' orbits and sizes, making future searches more effective.

The team found a noise signal in the data, likely caused by the star's surface activity, which made it harder to detect small moons. This noise increased the uncertainty in their measurements, limiting their sensitivity to only large moons, bigger than Ganymede, the largest moon in our Solar System. If this noise can be corrected in the future, JWST could detect moons similar in size to Earth's Moon. The results highlight the challenges of searching for exomoons and the importance of understanding and correcting for stellar noise in transit observations.

These findings provide new upper limits on the size of possible moons around TOI 700 d and e and set the stage for more sensitive searches in the future as data analysis techniques improve.

Key findings
- No exomoons detected around TOI 700 d and e
- Planet orbits and sizes measured with much higher precision
- Stellar noise limits sensitivity to large moons only
- Correcting for noise could allow detection of smaller, Luna-like moons
- Results guide future exomoon searches with JWST

Scientific study

The JWST Search for Earth-Luna Analogs: Upper Limits on Exomoons and Refined Ephemerides for TOI 700 d and e (external link)