Skip to main navigation Skip to search Skip to main content

Moderate nesting and cross-equatorial asymmetry of active regions in Solar Cycle 24

  • A. A. Norton
  • , A. Mendez
  • , R. Chen
  • , M. Dikpati
  • , S. Aswin Amirtha Raj
  • Stanford University

Research output: Contribution to journal › Article › peer-review

1 Scopus citations

Abstract

Solar Cycle 24 data are used to determine how often the Sun emerges sunspots in 'activity nests', i.e., regions where sunspots and active regions (ARs) repeatedly emerge. We use the Solar Photospheric Ephemeral Active Region (SPEAR) catalog created from Helioseismic and Magnetic Imager (HMI) data as well as the HMI Carrington Rotation maps of radial magnetic field, Br . The Sun shows moderate nesting behavior with 41% (48%) of AR magnetic flux found in Northern (Southern) hemispheric nests that are short-lived (average lifetimes similar to 3.3-4.0 months). Different rotation rates are used to search for nests that may not be evident 'by eye'. The maximum number of nests are found with slightly prograde rotational velocities, with significant nest flux also found at synodic 451-452 nHz prograde and 409-411 nHz retrograde frequencies. Nest patterns show strong hemispheric asymmetry, indicating that the physical origin of nests identified herein must also be asymmetric or antisymmetric across the equator.
Original languageEnglish
Article number48
Number of pages10
JournalJournal of Astrophysics and Astronomy
Volume47
Issue number2
Early online dateAug 2026
DOIs
StatePublished - Aug 20 2026

Keywords

  • Active regions
  • Dynamo
  • Sunspots

Fingerprint

Dive into the research topics of 'Moderate nesting and cross-equatorial asymmetry of active regions in Solar Cycle 24'. Together they form a unique fingerprint.

Cite this