The Right Thing To Do (tm) for asterosismology

Sarbani Basu (Yale) showed up and gave a great talk on the current state of helioseismology and asteroseismology. Before her talk—which showed off the awesome of Kepler and its ability to separate the different post-main-sequence phases of stars using normal modes—she was subjected to a two-hour grilling in CampHogg group meeting. We asked her about the narrowness of modes, the time dependence of amplitudes, the principal observables and how they are determined, and so on.

After her talk, Angus, Foreman-Mackey, and I argued about what a generative probabilistic model of a stellar light curve might do for asteroseismology. Right now the data analysis chain is: Take a periodogram of the data, identify modes, identify the maximum-amplitude frequency and various frequency differences, compare those to models thereof. An alternative approach would be: Take a model of a star, compute the expected frequency spectrum and variations around that, produce a probability distribution over lightcurves that could be produced by this spectrum, and then boom, likelihood function! We are nowhere close to having this, but some of the key applied-math pieces we might need are starting to come together.

At the end of the day I spoke at the Westchester Amateur Astronomers, about exoplanet search and discovery, and the prevalence of Earth analogs. I got absolutely great questions from the (very knowledgeable) crowd.

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