Solar Coronal Jets Extending to High Altitudes Observed During the 2017 August 21 Total Eclipse

TL;DR

This study observed solar coronal jets extending beyond 2 solar radii during the 2017 eclipse, revealing that typical polar jets reach high altitudes and likely contribute to the solar wind.

Contribution

First detailed observation linking EUV and white-light jets during a solar eclipse, showing that polar jets often reach high altitudes and escape as solar wind.

Findings

Six jets observed with speeds around 450 km/s

EUV jets precede white-light eclipse jets

Polar jets generally reach high altitudes and escape the Sun

Abstract

Coronal jets, which extend from the solar surface to beyond 2 $R_\odot$, were observed in the polar coronal hole regions during the total solar eclipse on 2017 August 21. In a time-series of white-light images of the corona spanning 70 minutes taken with our multi-site observations of this eclipse, six jets were found as narrow structures upwardly ejected with the apparent speed of about 450 km s$^{-1}$ in polar plumes. On the other hand, extreme-ultraviolet (EUV) images taken with the Atmospheric Image Assembly of the Solar Dynamics Observatory show that all of the eclipse jets were preceded by EUV jets. Conversely, all the EUV jets whose brightness is comparable to ordinary soft X-ray jets and which occurred in the polar regions near the eclipse period were observed as eclipse jets. These results suggest that ordinary polar jets generally reach high altitudes and escape from the Sun as part of the solar wind.