Kepler1625

Kepler-1625 is a star observed by NASA's Kepler mission and designated as part of the Kepler field of view. The system is known to host at least one planet candidate detected by the transit method, designated Kepler-1625 b. The planet is described as a gas giant with a relatively long orbital period around its host star.

In 2017–2018, researchers Teachey and Kipping proposed the existence of a large natural satellite around Kepler-1625 b, designated Kepler-1625 b i, based on anomalies in the transit signal such as timing and light-curve variations. The claim suggested a moon of substantial size, which, if confirmed, would mark one of the first exomoons identified beyond the Solar System. The idea generated significant interest but also debate within the exoplanet community, with questions about data quality, alternative explanations, and statistical significance.

Follow-up observations, including attempts with the Hubble Space Telescope, were undertaken to test the exomoon hypothesis. These efforts did not yield definitive confirmation of Kepler-1625 b i, and subsequent analyses have cast doubt on the robustness of the initial interpretation. As a result, the exomoon status remains unconfirmed, and the interpretation of the transit data is still debated.

The Kepler-1625 system is often cited in discussions of exomoon searches and illustrates the challenges of confirming moons around planets outside the Solar System. Ongoing developments in data analysis and future observations may further clarify the nature of this candidate system.