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The high occurrence rates of spiral arms and large central clearings inprotoplanetary disks, if interpreted as signposts of giant planets, indicatethat gas giants form commonly as companions to young stars ($<$ few Myr) atorbital separations of 10--300\,au. However, attempts to directly image thisgiant planet population as companions to more mature stars ($> 10$\, Myr) haveyielded few successes. This discrepancy could be explained if most giantplanets form "cold start," i.e., by radiating away much of their formationenergy as they assemble their mass, rendering them faint enough to eludedetection at later times. In that case, giant planets should be bright at earlytimes, during their accretion phase, and yet forming planets are detected onlyrarely through direct imaging techniques. Here we explore the possibility thatthe low detection rate of accreting planets is the result of episodic accretionthrough a circumplanetary disk. We also explore the possibility that thecompanion orbiting the Herbig Ae star HD~142527 may be a giant planetundergoing such an accretion outburst.

The Planetary Luminosity Problem: "Missing Planets" and the Observational Consequences of Episodic Accretion