Results 11 to 20 of about 3,012 (284)
Tests of Sunspot Number Sequences: 4. Discontinuities Around 1946 in Various Sunspot Number and Sunspot-Group-Number Reconstructions [PDF]
Solar Physics, 2016 In press with Solar ...
Lockwood, M., Owens, M. J., Barnard, L.
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Prediction of even and odd sunspot cycles [PDF]
Journal of Space Weather and Space Climate, 2023 Here we study the prediction of even and odd numbered sunspot cycles separately, thereby taking into account the Hale cyclicity of solar magnetism. We first show that the temporal evolution and shape of all sunspot cycles are extremely well-described by ...
Asikainen Timo, Mantere Jani
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A Deep Learning Approach for Automated Total Sunspot Number Estimation [PDF]
The Astrophysical JournalAccurate sunspot number estimation is essential for understanding the long-term evolution of solar activity and its impact on space weather. Sunspot numbers have been manually determined, leading to inconsistencies and observer-dependent biases.
Yimin Wang +5 more
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Relative Sunspot Number Observed from 2002 to 2011 at ButterStar Observatory [PDF]
Journal of Astronomy and Space Sciences, 2012 The ButterStar Observatory at the Dongducheon High School has been working for photographic observations of the Sun since October 16, 2002. In this study, we observed the Sun at the ButterStar observatory for 3,364 days from October 16, 2002 to December ...
Sung-Jin Oh, Heon-Young Chang
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Journal of Space Weather and Space Climate, 2017 We analyze the normalization factors (k′-factors) used to scale secondary observers to the Royal Greenwich Observatory (RGO) reference series of the Hoyt & Schatten (1998a, 1998b) group sunspot number (GSN).
Cliver Edward W.
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An upper limit prediction of the peak sunspot number for solar cycle 24
Journal of Space Weather and Space Climate, 2011 In this paper we address the prediction of the maximum sunspot number in solar cycle 24. We correlate the integral sunspot activity related to the variability of the cycle decrease speed in the declining phase with the height of the next sunspot maximum.
Van der Linden R., Podladchikova T.
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Sunspot Number Prediction Using Gated Recurrent Unit (GRU) Algorithm
IJCCS (Indonesian Journal of Computing and Cybernetics Systems), 2021 Sunspot is an area on photosphere layer which is dark-colored. Sunspot is very important to be researched because sunspot is affected by sunspot numbers, which present the level of solar activity. This research was conducted to make prediction on sunspot
Unix Izyah Arfianti +4 more
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The Ratio Between the Number of Sunspot and the Number of Sunspot Groups [PDF]
Geomagnetism and Aeronomy, 2017 Data from three solar observatories, Learmonth, Holloman, and San Vito, are used to study the variations in the average number of sunspots per sunspot group. It is found that the different types of sunspot groups and the number of sunspots in these groups have different solar cycle and cycle to cycle variations.
Georgieva, K. +3 more
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Relationship between group sunspot numbers and Wolf sunspot numbers [PDF]
Astronomische Nachrichten, 2010 AbstractContinuous wavelet transform and cross‐wavelet transform have been used to investigate the phase periodicity and synchrony of the monthly mean Wolf (Rz) and group (Rg) sunspot numbers during the period of June 1795 to December 1995. The Schwabe cycle is the only one common period in Rg and Rz, but it is not well‐defined in case of cycles 5–7 of
Li, Kejun, Liang, Hongfei
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Hemispheric sunspot numbers 1874–2020 [PDF]
Astronomy & Astrophysics, 2021 Context. Previous studies show significant north–south asymmetries for various features and indicators of solar activity. These findings suggest some decoupling between the two hemispheres over the solar cycle evolution, which is in agreement with dynamo theories.
Astrid M. Veronig +4 more
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