The new paper in Science Advances Evidence for a large exomoon orbiting Kepler-1625b (open access!) uses a sophisticated combination of occultation light curve simulation, signal processing and statistical analysis to show that there is a significant chance that they have identified an exomoon, a moon orbiting an exoplanet.
But it's too sophisticated for me to understand how this Hubble data indicates a potential moon. Terms like "detrending", "Markov chain Monte Carlo", and "Bayesian evidences" are beyond me.
Is it possible to choose one of those plots and add an arrow to say "this blip here, this is Kepler-1625b potential moon"? If not, is it possible to at least explain in a simple way what it is from this analysis that has led them to believe there may be a moon there?
Abstract:
Exomoons are the natural satellites of planets orbiting stars outside our solar system, of which there are currently no confirmed examples. We present new observations of a candidate exomoon associated with Kepler-1625b using the Hubble Space Telescope to validate or refute the moon’s presence. We find evidence in favor of the moon hypothesis, based on timing deviations and a flux decrement from the star consistent with a large transiting exomoon. Self-consistent photodynamical modeling suggests that the planet is likely several Jupiter masses, while the exomoon has a mass and radius similar to Neptune. Since our inference is dominated by a single but highly precise Hubble epoch, we advocate for future monitoring of the system to check model predictions and confirm repetition of the moon-like signal.