2016/12/22 by Chris Lowder, Jiong Qiu, Robert J. Leamon +1 · 85 citations
Physics and Astronomy · #Astro and Planetary Science #Astrobiology #Astronomy #Astrophysics #Corona (planetary geology) #Coronal hole #Coronal loop #Coronal mass ejection #Extreme ultraviolet #Heliosphere #Magnetic field #Nanoflares #Observatory #Optics #Physics #Polar #Solar and Space Plasma Dynamics #Solar observatory #Solar wind #Stellar, planetary, and galactic studies #astro-ph.SR
paper · pdf · doi:10.1007/s11207-016-1041-8
published in Solar Physics 292(1), 18 (Springer Science+Business Media) · Accepted for publication in Solar Physics
arxiv created 2016/12/22 · arxiv updated 2016/12/23 · openalex publication_date 2016/12/27 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
As the observational signature of the footprints of solar magnetic field lines open into the heliosphere, coronal holes provide a critical measure of the structure and evolution of these lines. Using a combination of Solar and Heliospheric Observatory/Extreme ultraviolet Imaging Telescope (SOHO/EIT), Solar Dynamics Observatory/Atmospheric Imaging Assembly (SDO/AIA), and Solar Terrestrial Relations Observatory/Extreme Ultraviolet Imager (STEREO/EUVI A/B) extreme ultraviolet (EUV) observations spanning 1996 – 2015 (nearly two solar cycles), coronal holes are automatically detected and characterized. Coronal hole area distributions show distinct behavior in latitude, defining the domain of polar and low-latitude coronal holes. The northern and southern polar regions show a clear asymmetry, with a lag between hemispheres in the appearance and disappearance of polar coronal holes.