Missing Transits in Kepler

One of the more amusing SETI articles in recent memory is one suggesting lasers could be used to “cloak” a planet’s transit, by essentially filling in the missing starlight occulted by the planet. This raises an interesting observable question: Do we ever see transits go missing?

There have been examples of eclipses (i.e. two stars) changing depths over the course of the Kepler mission. These are neat, and usually attributed to the viewing angle of the system changing.

Transit Timing Variations (TTVs) are all the rage, as the slow drift/change of transit occurrence times points to additional planets/bodies in the system. What you observe is a periodic transit event slowly falling ahead/behind schedule as the 3rd body moves around it.

However this idea is much simpler, and driven by the SETI question: Do any transits fail to show up when we’d expect them to?

Game plan:

  • Get list of all available transiting planets in Kepler without transit timing variations (TTVs)
  • Obtain long cadence (30-min) light curves for each system
  • Using published periods & times for transits, step through light curve and verify transit is present if data is available (i.e. missing data doesn’t count)

On some level this is a “reality check” exercise. I would basically not expect to find any published planets to have missing transits, as I think this would cause undue scatter in the phase-folded data that would have led to their rejection. However given the entertaining SETI angle, it does seem worth it to at least check!