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Related papers: Solar cycle 25: another moderate cycle?

200 papers

Prediction of the Sun's magnetic activity is important because of its effect on space environment and climate. However, recent efforts to predict the amplitude of the solar cycle have resulted in diverging forecasts with no consensus.…

Solar and Stellar Astrophysics · Physics 2012-12-07 Bidya Binay Karak , Dibyendu Nandy

The 11-year cycle of solar activity follows Hale's law by reversing the magnetic polarity of leading and following sunspots in bipolar regions during the minima of activity. In the 1996-97 solar minimum, most solar activity emerged in…

Astrophysics · Physics 2009-10-31 E. E. Benevolenskaya , J. T. Hoeksema , A. G. Kosovichev , P. H. Scherrer

The solar magnetic activity cycle is responsible for periodic episodes of severe space weather, which can perturb satellite orbits, interfere with communications systems, and bring down power grids. Much progress has recently been made in…

Astrophysics · Physics 2007-05-23 T. S. Metcalfe , T. J. Henry , M. Knolker , D. R. Soderblom

The concept of degree of similarity ({\eta}) is proposed to quantitatively describe the similarity of a parameter (e.g. the maximum amplitude Rmax) of a solar cycle relative to a referenced one, and the prediction method of similar cycles…

Solar and Stellar Astrophysics · Physics 2015-06-03 Z. L. Du , H. N. Wang

Although there are now some tentative signs that the start of cycle 24 has begun there is still considerable interest in the somewhat unusual behaviour of the current solar minimum and the apparent delay in the true start of the next cycle.…

Solar and Stellar Astrophysics · Physics 2010-03-23 Stephen Fletcher , Roger New , Anne-Marie Broomhall , William Chaplin , Yvonne Elsworth

Observations show that the photospheric solar magnetic dipole usually does not vanish during the reversal of the solar magnetic field, which occurs in each solar cycle. In contrast, mean-field solar dynamo models predict that the dipole…

Solar and Stellar Astrophysics · Physics 2014-09-05 V. V. Pipin , D. Moss , D. D. Sokoloff , J. T. Hoeksema

Solar active regions (ARs) determine solar polar fields and cause solar cycle variability within the framework of the Babcock-Leighton (BL) dynamo. The contribution of an AR to the polar field is measured by its dipole field, which results…

Solar and Stellar Astrophysics · Physics 2025-06-03 Ruihui Wang , Jie Jiang , Yukun Luo

Context: Observations indicate that the `quiet' solar photosphere outside active regions contains considerable amounts of magnetic energy and magnetic flux, with mixed polarity on small scales. The origin of this flux is unclear. Aims: We…

Astrophysics · Physics 2009-11-13 A. Voegler , M. Schuessler

The dependence of the sources and properties of the near-Earth solar wind on solar cycle activity is an important issue in solar and space physics. We use the improved two-step mapping procedure that takes into account the initial…

Solar and Stellar Astrophysics · Physics 2024-07-02 Xinzheng Shi , Hui Fu , Zhenghua Huang , Limei Yan , Chi Ma , Chenxi Huangfu , Hongqiang Song , Lidong Xia

The Sun's variability is controlled by the progression and interaction of the magnetized systems that form the 22-year magnetic activity cycle (the "Hale Cycle'') as they march from their origin at $\sim$55 degrees latitude to the equator,…

Solar and Stellar Astrophysics · Physics 2021-12-07 Robert Leamon , Scott McIntosh , Alan Title

Using the polar vector magnetic field data observed by Hinode from 2012 to 2021, we study the long-term variations of the magnetic flux, the flux proportion of different polarities, and the magnetic inclination with respect to the local…

Solar and Stellar Astrophysics · Physics 2025-09-25 Shuhong Yang , Chunlan Jin , Qiao Song , Yuzong Zhang , Yin Li , Yijun Hou , Ting Li , Guiping Zhou , Yuanyong Deng , Jingxiu Wang

This paper presents time series observations and analysis of broadband night sky airglow intensity 4 September 2018 through 30 April 2020. Data were obtained at 5 sites spanning more than 8500 km during the historically deep minimum of…

Solar and Stellar Astrophysics · Physics 2021-12-06 Albert D. Grauer , Patricia A. Grauer

Aims: To investigate solar polar fields during cycle 24, using measurements of solar magnetic fields in the latitude range 55 - 90 degree and 78 - 90 degree, to report a prolonged and unusual hemispheric asymmetry in the polar field…

Solar and Stellar Astrophysics · Physics 2018-10-24 P. Janardhan , K. Fujiki , M. Ingale , Susanta Kumar Bisoi , Diptiranjan Rout

The Parker Solar Probe (PSP) and Solar Orbiter missions are designed to make groundbreaking observations of the Sun and interplanetary space within this decade. We show that a particularly interesting in situ observation of an…

To estimate the hemispheric flux generation rate of the large-scale radial magnetic field in the Solar Cycles 23 and 24, we use the photospheric observations of the solar magnetic fields and results of the mean-field dynamo models. Results…

Solar and Stellar Astrophysics · Physics 2024-08-12 V. V. Pipin

Long-term sunspot observations and solar activity reconstructions reveal that the Sun occasionally slips into quiescent phases known as solar grand minima, the dynamics during which is not well understood. We use a flux transport dynamo…

Solar and Stellar Astrophysics · Physics 2022-09-30 Chitradeep Saha , Sanghita Chandra , Dibyendu Nandy

The first significant sunquake event of Solar Cycle 25 was observed during the X1.5 flare of May 10, 2022, by the Helioseismic and Magnetic Imager (HMI) onboard the Solar Dynamics Observatory. We perform a detailed spectro-polarimetric…

Solar and Stellar Astrophysics · Physics 2023-09-15 Alexander G. Kosovichev , Viacheslav M. Sadykov , John T. Stefan

Solar inter-network magnetic field is the weakest component of solar magnetism, but contributes most of the solar surface magnetic flux. The study on its origin has been constrained by the inadequate tempo-spatial resolution and sensitivity…

Solar and Stellar Astrophysics · Physics 2015-05-26 Chunlan Jin , Jingxiu Wang

We present independent observations of the solar-cycle variation of flows near the solar surface and at a depth of about 60 Mm, in the latitude range $\pm45^\circ$. We show that the time-varying components of the meridional flow at these…

Astrophysics · Physics 2009-11-13 L. Gizon , M. Rempel

We examine the solar-cycle variation of the power in the low-degree helioseismic modes by looking at binned power spectra from 45 years of observations with the Birmingham Solar Oscillations Network, which provides a more robust estimate of…

Solar and Stellar Astrophysics · Physics 2022-06-22 Rachel Howe , W. J. Chaplin , Y. P. Elsworth , S. J. Hale , M. B. Nielsen