Chromospheric Anemone Jets as Evidence of Ubiquitous Reconnection

TLDR

The heating of the solar chromosphere and corona remains a long‑standing puzzle, and the inverted‑Y shape of small chromospheric jets resembles coronal x‑ray anemone jets. Hinode observations reveal ubiquitous chromospheric anemone jets outside sunspots, measuring 2000–5000 km long, 150–300 km wide, and moving at 10–20 km s⁻¹, whose inverted‑Y shape indicates small‑scale magnetic reconnection that may contribute to chromospheric and coronal heating.

Abstract

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.