학술논문

Fleeting Small-scale Surface Magnetic Fields Build the Quiet-Sun Corona
Document Type
article
Source
The Astrophysical Journal Letters, Vol 956, Iss 1, p L1 (2023)
Subject
Solar extreme ultraviolet emission
Solar photosphere
Solar coronal heating
Solar magnetic fields
Solar magnetic reconnection
Magnetohydrodynamics
Astrophysics
QB460-466
Language
English
ISSN
2041-8213
2041-8205
97532479
Abstract
Arch-like loop structures filled with million Kelvin hot plasma form the building blocks of the quiet-Sun corona. Both high-resolution observations and magnetoconvection simulations show the ubiquitous presence of magnetic fields on the solar surface on small spatial scales of ∼100 km. However, the question of how exactly these quiet-Sun coronal loops originate from the photosphere and how the magnetic energy from the surface is channeled to heat the overlying atmosphere is a long-standing puzzle. Here we report high-resolution photospheric magnetic field and coronal data acquired during the second science perihelion of Solar Orbiter that reveal a highly dynamic magnetic landscape underlying the observed quiet-Sun corona. We found that coronal loops often connect to surface regions that harbor fleeting weaker, mixed-polarity magnetic field patches structured on small spatial scales, and that coronal disturbances could emerge from these areas. We suggest that weaker magnetic fields with fluxes as low as 10 ^15 Mx and/or those that evolve on timescales less than 5 minutes are crucial to understanding the coronal structuring and dynamics.