Sunspot features in the transition region

The newly launched IRIS spacecraft provides us with an unprecedented view of sunspots in the upper layers of the solar atmosphere, especially in the highly dynamic transition region. We analyze several interesting features related to sunspots, such as oscillations, and bright emission ribbons appearing above a sunspot's umbra. These emission ribbons resemble flare ribbons and with IRIS' high spatial resolution, locations of enhanced heating along the ribbon can be identified. The Mg II spectra significantly change their shape in the umbra, which will offer insights into the temperature structuring of the transition region.