Small-scale jetlike features in penumbral chromospheres.

We observed fine-scale jetlike features, referred to as penumbral microjets, in chromospheres of sunspot penumbrae. The microjets were identified in image sequences of a sunspot taken through a Ca II H-line filter on the Solar Optical Telescope on board the Japanese solar physics satellite Hinode. The microjets' small width of 400 kilometers and short duration of less than 1 minute make them difficult to identify in existing observations. The microjets are possibly caused by magnetic reconnection in the complex magnetic configuration in penumbrae and have the potential to heat the corona above a sunspot.