The heating of the solar chromosphere and corona is a long-standing puzzle in solar physics. Hinode observations show the ubiquitous presence of chromospheric anemone jets outside sunspots in active regions. They are typically 3 to 7 arc seconds = 2000 to 5000 kilometers long and 0.2 to 0.4 arc second = 150 to 300 kilometers wide, and their velocity is 10 to 20 kilometers per second. These small jets have an inverted Y-shape, similar to the shape of x-ray anemone jets in the corona. These features imply that magnetic reconnection similar to that in the corona is occurring at a much smaller spatial scale throughout the chromosphere and suggest that the heating of the solar chromosphere and corona may be related to small-scale ubiquitous reconnection.
@article{arxiv.0810.3974,
title = {Chromospheric Anemone Jets as Evidence of Ubiquitous Reconnection},
author = {Kazunari Shibata and Tahei Nakamura and Takuma Matsumoto and Kenichi Otsuji and Takenori J. Okamoto and Naoto Nishizuka and Tomoko Kawate and Hiroko Watanabe and Shin'ichi Nagata and Satoru UeNo and Reizaburo Kitai and Satoshi Nozawa and Saku Tsuneta and Yoshinori Suematsu and Kiyoshi Ichimoto and Toshifumi Shimizu and Yukio Katsukawa and Theodore D. Tarbell and Thomas E. Berger and Bruce W. Lites and Richard A. Shine and Alan M. Title},
journal= {arXiv preprint arXiv:0810.3974},
year = {2009}
}