Research Highlights
Research Highlights
A selection of highlights culled from publications by HAO staff.

Comparative Solar Minima Using the McIntosh Archive
I. M. Hewins, S. E. Gibson, D. F. Webb, R. H. McFadden, T. A. Kuchar, B. A. Emery present the full Archive for the first time, as well as a supplement set of related maps created for the 2019-2020 solar minimum. They use a study of cross-calibrated EUV and He-I 10830 \AA\ coronal holes to better understand the connection between the nature of coronal holes during the WHPI solar minimum and the earlier minima in the main Archive.

Influence of Stratosphere Polar Vortex Variability on the Mesosphere, Thermosphere, and Ionosphere
Nick Pedatella used WACCM-X to investigate the influence of stratosphere polar vortex variability on the mesosphere, thermosphere, and ionosphere during Northern Hemisphere winter. Based on 40 simulated Northern Hemisphere winters, the mesosphere and lower thermosphere (MLT) residual circulation is found to depend on whether the stratosphere polar vortex is strong or weak.

Hybrid data-driven magnetofrictional and magnetohydrodynamic simulations of an eruptive solar active region
Andrey N. Afanasyev, Yuhong Fan, Maria D. Kazachenko, and Mark C.M. Cheung present first results of the hybrid data–driven magnetofrictional (MF) and data–constrained magnetohydrodynamic (MHD) simulations of solar active region NOAA 11158, which produced an X-class flare and coronal mass ejection on 2011 February 15. We conclude that the combination of the data–driven MF and data–constrained MHD simulations is a useful practical tool for understanding the 3D magnetic structures of real solar ARs that are unobservable otherwise.

Science opportunities with solar sailing smallsats
Sarah Gibson, et al. witnessed how the synergy of small satellite technology and solar sailing propulsion enables new missions. Together, small satellites with lightweight instruments and solar sails offer affordable access to deep regions of the solar system, also making it possible to realize hard-to-reach trajectories that are not constrained to the ecliptic plane.

A Comprehensive Radiative Magnetohydrodynamics Simulation of Active Region Scale Flux Emergence from the Convection Zone to the Corona
Feng Chen, Matthias Rempel, and Yuhong Fan present a comprehensive radiative magnetohydrodynamic simulation of the quiet Sun and large solar active regions. This study provides a comprehensive view of the active region corona, such as coronal loops of various lengths and temperatures, mass circulation by evaporation and condensation, and eruptions from jets to large-scale mass ejections.

A Mosaic of the inner heliosphere:
Sarah E. Gibson, et al. provide an expansive mosaic of observations spanning from the Sun, through interplanetary space, to the magnetospheric response and subsequent effects on the ionosphere-thermosphere-mesosphere (ITM) system. To accomplish this, a diverse set of observational datasets are utilized and focused on two long-lived coronal holes and their varying impact in sculpting the heliosphere and driving of the magnetospheric system.

Data-driven Radiative Magnetohydrodynamics Simulations with the MURaM Code
Feng Chen, Mark C.M. Cheung, Matthias Rempel, and Georgios Chintzoglou present a method of conducting data-driven simulations of solar active regions and flux emergence with the MURaM radiative magnetohydrodynamics (MHD) code. This method helps to understand the evolution of magnetic field in a more realistic coronal environment and to link the magnetic structures to observable diagnostics.

Small-scale dynamos: From idealized models to solar and stellar applications
Matthias Rempel, Tanayveer Bhatia, Luis Bellot Rubio, and Maarit J. Korpi-Lagg review small-scale dynamo processes that are responsible for magnetic field generation on scales comparable to and smaller than the energy carrying scales of turbulence. We provide a review of critical observation of quiet Sun magnetism, which have provided strong support for the operation of a small-scale dynamo in the solar photosphere and convection zone.

Impact of strong and weak stratospheric polar vortices on geomagnetic solar and lunar tides
N. M. Pedatella, et al. investigate the impact of strong and weak stratospheric polar vortices on geomagnetic semidiurnal solar and lunar tides during Northern Hemisphere (NH) winters using ground-based magnetic field observations at the Huancayo (-12.05° N, 284.67° E; magnetic latitude: -0.6° N) equatorial observatory.