In this thesis I focus on two topics: planet-disk interaction and solar convection. These two seemingly separate topics are connected via a similar separation of timescales. Planets excite spiral waves in their disks on fast timescales compared to the time for the disk to viscously adjust to the angular momentum...
We present initial results from Hertz/VPM, the first submillimeter polarimeter employing the dual Variable-delay Polarization Modulator (dual-VPM). This device differs from previously used polarization modulators in that it operates in translation rather than mechanical rotation. We discuss the basic theory behind this device, and its potential advantages over the commonly...