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Related papers: Revisited sunspot data: A new scenario for the ons…

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The solar cycle periodically reshapes the magnetic structure and radiative output of the Sun and determines its impact on the heliosphere roughly every 11 years. Besides this main periodicity, it shows century-long variations (including…

Solar and Stellar Astrophysics · Physics 2022-03-23 A. Munoz-Jaramillo , J. M. Vaquero

Aims: Although the time of the Maunder minimum (1645--1715) is widely known as a period of extremely low solar activity, claims are still debated that solar activity during that period might still have been moderate, even higher than the…

The Maunder Minimum corresponds to a prolonged minimum of solar activity a phenomenon that is of particular interest to many branches of natural and social sciences commonly considered to extend from 1645 until 1715. However, our knowledge…

Solar and Stellar Astrophysics · Physics 2015-06-19 J. M. Vaquero , R. M. Trigo

One of the most striking aspects of the 11-year sunspot cycle is that there have been times in the past when some cycles went missing, a most well-known example of this being the Maunder minimum during 1645-1715. Analyses of cosmogenic…

Solar and Stellar Astrophysics · Physics 2014-04-09 Arnab Rai Choudhuri , Bidya Binay Karak

Using a reconstruction of sunspot numbers stretching over multiple millennia, we analyze the statistics of the occurrence of grand minima and maxima and set new observational constraints on long-term solar and stellar dynamo models. We…

Astrophysics · Physics 2014-11-18 I. G. Usoskin , S. K. Solanki , G. A. Kovaltsov

The Maunder minimum (MM) of greatly reduced solar activity took place in 1645-1715, but the exact level of sunspot activity is uncertain as based, to a large extent, on historical generic statements of the absence of spots on the Sun. Here…

Solar and Stellar Astrophysics · Physics 2015-05-11 J. M. Vaquero , G. A. Kovaltsov , I. G. Usoskin , V. M. S. Carrasco , M. C. Gallego

The Maunder Minimum (1645-1715 approximately) was a period of very low solar activity and a strong hemispheric asymmetry, with most of sunspots in the southern hemisphere. In this paper, two data sets of sunspot latitudes during the Maunder…

Solar and Stellar Astrophysics · Physics 2015-01-27 J. M. Vaquero , J. M. Nogales , F. Sánchez-Bajo

Solar activity in all its varied manifestations is driven by the magnetic field. Particularly important for many purposes are two global quantities, the Sun's total and open magnetic flux, which can be computed from sunspot number records…

Solar and Stellar Astrophysics · Physics 2021-06-09 N. A. Krivova , S. K. Solanki , B. Hofer , C. -J. Wu , I. G. Usoskin , R. Cameron

The 11-yr cycle of sunspots undergo amplitude modulation over longer timescales. As a part of this long-term modulation in solar activity, the decennial rhythm occasionally breaks, with quiescent phases with very few sunspots observed over…

Solar and Stellar Astrophysics · Physics 2025-09-05 Chitradeep Saha , Sanghita Chandra , Dibyendu Nandy

The occurrence of grand minima like the Maunder minimum is an intriguing aspect of the sunspot cycle. We use the flux transport dynamo model to explain the grand minima, showing that they arise when either the poloidal field or the…

Solar and Stellar Astrophysics · Physics 2013-07-23 Bidya Binay Karak , Arnab Rai Choudhuri

We describe a revised collection of the number of sunspot groups from 1610 to the present. This new collection is based on the work of Hoyt and Schatten (Solar Phys. 179, 189, 1998). The main changes are the elimination of a considerable…

Solar and Stellar Astrophysics · Physics 2023-01-06 J. M. Vaquero , L. Svalgaard , V. M. S. Carrasco , F. Clette , L. Lefèvre , M. C. Gallego , R. Arlt , A. J. P. Aparicio , J. -G. Richard , R. Howe

The recent paucity of sunspots and the delay in the expected start of Solar Cycle 24 have drawn attention to the challenges involved in predicting solar activity. Traditional models of the solar cycle usually require information about the…

Solar and Stellar Astrophysics · Physics 2013-12-05 Mercedes T. Richards , Michael L. Rogers , Donald St. P. Richards

The sunspot groups have been observed since 1610 and their numbers have been used for evaluating the amplitude of solar activity. Daniel M\"ogling recorded his sunspot observations for more than 100 days in 1626 - 1629 and formed a…

Solar and Stellar Astrophysics · Physics 2021-02-09 Hisashi Hayakawa , Tomoya Iju , Koji Murata , Bruno P. Besser

Two important sources of information about sunspots in the Maunder minimum are the Sp\"orer catalog and observations of the Paris observatory, which cover in total the last quarter of the 17th and the first two decades of the 18th century.…

Solar and Stellar Astrophysics · Physics 2017-02-01 V. G. Ivanov , E. V. Miletsky

The solar activity during the Maunder Minimum (MM; 1645 -- 1715) has been considered significantly different from the one captured in modern observations, in terms of sunspot group number and sunspot positions, whereas its actual amplitudes…

Solar and Stellar Astrophysics · Physics 2020-10-01 Hisashi Hayakawa , Tomoya Iju , Shoma Uneme , Bruno P. Besser , Shunsuke Kosaka , Shinsuke Imada

Using a summary curve of two eigen vectors of solar magnetic field oscillations derived with Principal Components Analysis (PCA) from synoptic maps for solar cycles 21-24 as a proxy of solar activity, we extrapolate this curve backwards…

Solar and Stellar Astrophysics · Physics 2021-09-20 V. V. Zharkova , S. J. Shepherd , E. Popova , S. I Zharkov

On a centennial timescale, solar activity was quantified based on records of instrumental sunspot observations. This article briefly discusses several aspects of the recent archival investigations of historical sunspot records in the 17th…

Solar and Stellar Astrophysics · Physics 2025-02-21 Hisashi Hayakawa

The planetary hypothesis of the solar cycle is an old idea in which the gravitational influence of the planets has a non-negligible effect on the causes of the solar magnetic cycle. In this work we looked for a possible causal link in…

Earth and Planetary Astrophysics · Physics 2012-07-24 Rodolfo Gustavo Cionco , Rosa Hilda Compagnucci

Sunspot engravings and measurements in 1660-1676 are analyzed to retrieve sunspot area and heliocoordinates. Based on these data, we revise the Hoyt and Schatten (The role of the sun in climate change, 1997) hypothesis of long-lived…

Solar and Stellar Astrophysics · Physics 2025-02-25 Nadezhda Zolotova , Mikhail Vokhmyanin

A solar-type dynamo model in a spherical shell is developed with allowance for random dependence of the poloidal field generation mechanism on time and latitude. The model shows repeatable epochs of strongly decreased amplitude of magnetic…

Solar and Stellar Astrophysics · Physics 2015-06-17 S. V. Olemskoy , L. L. Kitchatinov
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