The three-dimensional solar wind at solar activity minimum

Are coronal holes the only source of fast solar wind at solar minimum?

[1] A two-dimensional (2-D) MHD model of an Alfvén-wave-driven solar wind in the heliospheric meridional plane is presented whereby the consequences of a magnetic field distribution at the Sun that digresses from the standard dipole structure, often used in 2-D MHD models, are explored. The latitudinal distribution of open magnetic flux is specified at the solar surface, with a clear distinctio...

Implications of the Recent Low Solar Minimum for the Solar Wind during the Maunder Minimum

The behavior of the Sun and near-Earth space during grand solar minima is not understood; however, the recent long and low minimum of the decadal-scale solar cycle gives some important clues, with implications for understanding the solar dynamo and predicting space weather conditions. The speed of the near-Earth solar wind and the strength of the interplanetary magnetic field (IMF) embedded wit...

The distribution of solar wind speeds during solar minimum: Calibration for numerical solar wind modeling constraints on the source of the slow solar wind

[1] It took the solar polar passage of Ulysses in the early 1990s to establish the global structure of the solar wind speed during solar minimum. However, it remains unclear if the solar wind is composed of two distinct populations of solar wind from different sources (e.g., closed loops which open up to produce the slow solar wind) or if the fast and slow solar wind rely on the superradial exp...

Solar Wind Composition Associated with the Solar Activity

Sources of solar wind over the solar activity cycle

Fast solar wind has been recognized, about 40 years ago, to originate in polar coronal holes (CHs), that, since then, have been identified with sources of recurrent high speed wind streams. As of today, however, there is no general consensus about whether there are, within CHs, preferential locations where the solar wind is accelerated. Knowledge of slow wind sources is far from complete as wel...