Results 91 to 100 of about 14,709 (209)

Turbulence in a Coronal Loop Excited by Photospheric Motions

Atmosphere, 2020
Photospheric motions are believed to be the source of coronal heating and of velocity fluctuations detected in the solar corona. A numerical model, based on the shell technique applied on reduced magnetohydrodynamics equations, is used to represent ...
Giuseppina Nigro, Francesco Malara, Antonio Vecchio, Leonardo Primavera, Francesca Di Mare, Vincenzo Carbone, Pierluigi Veltri   +6 more
doaj   +1 more source

Coronal Loop Heating by Nearly Incompressible Magnetohydrodynamic and Reduced Magnetohydrodynamic Turbulence Models

The Astrophysical Journal, 2023
The transport of waves and turbulence beyond the photosphere is central to the coronal heating problem. Turbulence in the quiet solar corona has been modeled on the basis of the nearly incompressible magnetohydrodynamic (NI MHD) theory to describe the ...
M. S. Yalim, G. P. Zank, M. Asgari-Targhi   +2 more
doaj   +1 more source

Network oscillations at the boundary of an equatorial coronal hole [PDF]

, 2008
We investigate intensity oscillations observed simultaneously in the quiet chromosphere and in the corona, above an enhanced network area at the boundary of an equatorial coronal hole. A Fourier analysis is applied to a sequence of images observed in the
Banerjee, Brynildsen, Cauzzi, Curdt, Damé, De Moortel, De Moortel, De Pontieu, De Pontieu, De Pontieu, DeForest, Dowdy, Doyle, Fludra, Fossum, Gabriel, H. Tian, Hansteen, Jefferies, Kariyappa, Krijger, L.-D. Xia, Lites, McAteer, McAteer, McIntosh, McIntosh, O'Shea, Ofman, Patsourakos, Peter, Peter, Popescu, Sakurai, Srivastava, Tian, Ugarte-Urra, Ugarte-Urra, Vecchio, Withbroe, Xia   +40 more
core   +1 more source

Solar Soft X‐Ray Proxy Derived From Observed Auger Photoelectrons by MGS and a 1999–2006 Flare Catalog at Mars

Geophysical Research Letters, Volume 53, Issue 3, 16 February 2026.
Abstract This study uses a novel approach to infer the solar soft X‐ray (SXR) irradiance from Auger photoelectron fluxes. Solar SXR irradiance is highly variable, particularly during solar flares. Solar SXR photons at ∼< ${\sim} < $2.5 nm produce oxygen Auger photoelectrons by photoionizing atmospheric constituents. More specifically, we derive the fit
Shaosui Xu, Edward M. Thiemann, David L. Mitchell, Phillip C. Chamberlin   +3 more
wiley   +1 more source

Newly Discovered Global Temperature Structures in the Quiet Sun at Solar Minimum [PDF]

, 2012
Magnetic loops are building blocks of the closed-field corona. While active region loops are readily seen in images taken at EUV and X-ray wavelengths, quiet Sun loops are seldom identifiable and therefore difficult to study on an individual basis.
Alberto M. Vásquez, Antiochos, Aschwanden, Aschwanden, Craig, Enrico Landi, Feldman, Frazin, Frazin, Frazin, Landi, Pasachoff, Patsourakos, Reale, Richard A. Frazin, Schrijver, Schrijver, Tamas I. Gombosi, Tripathi, Tóth, Viall, Wang, Ward B. Manchester, Warren, Winebarger, Zhenguang Huang   +25 more
core   +3 more sources

A New Method for Probabilistic Spatiotemporal Forecasts of Solar Soft X‐Ray “S‐Class” (>X10) Superflares

Journal of Geophysical Research: Space Physics, Volume 131, Issue 2, February 2026.
Abstract Solar superflares of S‐class (>X10 in soft X‐rays) pose extreme space weather hazards, yet their prediction remains a fundamental challenge owing to their rapid and transient natures and the limitations of conventional event‐based forecasts. We introduce for the first time, a probabilistic spatiotemporal framework designed to identify extended
V. M. Velasco Herrera, G. Velasco Herrera, W. Soon, A. Özgüç, N. Babynets, A. Tlatov, M. Švanda, S. Qiu, S. Baliunas, B. Kotan, G. González González, L. A. Bautista Flores, M. Pazos   +12 more
wiley   +1 more source

Are Heating Events in the Quiet Solar Corona Small Flares? Multiwavelength Observations of Individual Events [PDF]

Solar Physics, 2000
Temporary enhancements of the coronal emission measure in a quiet region have been shown to constitute a significant energy input. Here some relatively large events are studied for simultaneous brightenings in transition region lines and in radio emission. Associated emissions are discussed and tested for characteristics known from full-sized impulsive
Krucker, Sam, Benz, Arnold O.
openaire   +2 more sources

MAVEN EUVM Data Products for Space Weather at Mars

Space Weather, Volume 24, Issue 2, February 2026.
Abstract Space weather monitoring is critical to protect not only our technological assets in space, but also mitigate disruptions to life and society that depends on these vulnerable assets. Significant attention and resources have been dedicated to space weather monitoring at Earth, but little attention to date has been paid to planetary space ...
P. C. Chamberlin, G. A. DiBraccio, R. J. Borelli, Y. M. Collado‐Vega, S. Curry, F. G. Eparvier, C. O. Lee, M. L. Mays, E. M. B. Thiemann, C. Wiegand   +9 more
wiley   +1 more source

Observations of Mini Coronal Dimmings Caused by Small-scale Eruptions in the Quiet Sun

The Astrophysical Journal Letters, 2023
Small-scale eruptions could play an important role in coronal heating, generation of solar energetic particles (SEPs), and mass source of the solar wind.
Rui Wang, Ying D. Liu, Xiaowei Zhao, Huidong Hu   +3 more
doaj   +1 more source

Inferring the Coronal Density Irregularity from EUV Spectra [PDF]

, 2016
Understanding the density structure of the solar corona is important for modeling both coronal heating and the solar wind. Direct measurements are difficult because of line-of-sight integration and possible unresolved structures.
Hahn, Michael, Savin, Daniel Wolf
core   +3 more sources