Results 21 to 30 of about 8,610,015 (269)
Sunspot observations at Kawaguchi Science Museum: 1972 – 2013
Geoscience Data Journal, 2023 Individual sunspot observations have formed a ground basis of international sunspot number, a unique reference for long‐term solar variability in the centennial timescale.
Hisashi Hayakawa +5 more
doaj +1 more source
ANALYSIS OF SUNSPOT NUMBER FLUCTUATIONS [PDF]
Fractals, 2004 Monthly averages of the sunspot number visible on the sun, observed from 1749, Zurich Observatory, and from 1848 other observatories, have been analyzed. This time signal presents a frequency power spectra with a clear 1/fα behavior with α≃0.8±0.2.
Fanchiotti, H. +3 more
openaire +2 more sources
Von Lindener's sunspot data: sunspot group number and individual sunspot number
, 2023 Hayakawa et al. (2023) derived sunspot group number and individual sunspot number from von Liindener's records. These data have been extracted from von Lindener's manuscript (Akc.1985/15) in the Library of Wrocław University and Bode (1819).
早川, 尚志, Hayakawa, Hisashi
core +1 more source
Ratio Mathematica, 2020 The 11 year sunspot number cycle has been a fascinating phenomenon for many scientists in the last three centuries. Various mathematical functions have been used for modelling the 11 year sunspot number cycles.
Amaranathan Sabarinath +2 more
doaj +1 more source
Katsue Misawa's sunspot data: sunspot group number and individual sunspot number
, 2023 These files show Katsue Misawa's sunspot observations with her 3-inch rafractor telescope from 1921 to 1934.
早川, 尚志, Hayakawa, Hisashi
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Long-term solar activity explored with wavelet methods [PDF]
Annales Geophysicae, 2006 Long-term solar activity has been studied with a set of wavelet methods. The following indicators of long-term solar activity were used; the group sunspot number, the sunspot number, and the 14C production rate.
H. Lundstedt +3 more
doaj +1 more source
An Overview of Sunspot Observations in the Early Maunder Minimum: 1645 – 1659
, 2023 Hayakawa et al. (2024) derived sunspot group number and individual sunspot number in the early Maunder Minimum. See their details in Hayakawa et al.
早川, 尚志, Hayakawa, Hisashi
core +1 more source
Change of Sunspot Groups Observed from 2002 to 2011 at ButterStar Observatory [PDF]
Journal of Astronomy and Space Sciences, 2012 Since the development of surface magnetic features should reflect the evolution of the solar magnetic field in the deep interior of the Sun, it is crucial to study properties of sunspots and sunspot groups to understand the physical processes working ...
Sung-Jin Oh, Heon-Young Chang
doaj +1 more source
The Astrophysical Journal Supplement Series, 2023 In this paper, an optimized long short-term memory model is proposed to deal with the smoothed monthly F _10.7 and nonsmoothed monthly sunspot area (SSA) data, aiming to forecast the peak amplitude of both solar activities and the occurring time for ...
Hongbing Zhu +3 more
doaj +1 more source
Katsue Misawa's sunspot drawngs: 1921 -- 1934
, 2023 These files show Katsue Misawa's sunspot observations with her 3-inch rafractor telescope from 1921 to 1934. Their original records are preserved in Misawa Memorial Archives.
Misawa, Katsue, 三澤, 勝衛
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