Solar cycle

Definitions

  • Webster's Revised Unabridged Dictionary
    • Solar cycle a period of 28 years, at the end of which time the days of the month return to the same days of the week. The dominical or Sunday letter follows the same order; hence the solar cycle is also called the cycle of the Sunday letter. In the Gregorian calendar the solar cycle is in general interrupted at the end of the century.
    • Solar cycle See under Cycle.
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Usage

In literature:

Perhaps the theory of solar magnetic influence upon the weather is best known in connection with the ``sun-spot cycle.
"Curiosities of the Sky" by Garrett Serviss
SOLAR CYCLE, a period of 28 years, within which the first day of the year passes successively through the same sequence of week-days.
"The Nuttall Encyclopaedia" by Edited by Rev. James Wood
A cycle of 19 years, which contains 235 lunations, and results in a correspondence of the solar and lunar years.
"The Sailor's Word-Book" by William Henry Smyth
Forty-nine years make a convenient luni-solar cycle, reconciling the lunar month and the tropical solar year.
"The Astronomy of the Bible" by E. Walter Maunder
Cycles used in chronology are three: The solar cycle, the lunar cycle, and the cycle of indiction.
"Our Calendar" by George Nichols Packer
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In news:

In fact, the X6.9-class super flare was the largest in the star's current 11-year solar cycle (which began in 2008), and larger than any since 2006.
When the solar cycle is at a minimum, active regions are small and rare and few solar flares are detected.
The increased solar activity is part of an upswing during the sun's normal 11-year cycle.
While Solar Cycle 24 is making the high bands the focal point for HF operators, 160 meters .
One of the two flares that erupted yesterday was classed as a X5.4 – making it the second largest solar flare in the current solar cycle.
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In science:

We have already seen from the results presented in the previous section that the strength of magnetic buoyancy (fb ) has a strong influence on the dynamo period (and thus on the efficiency) of the solar cycle.
Characteristics Of A Magnetic Buoyancy Driven Solar Dynamo Model
Predicting the strength of solar cycle 24 using a fluxtransport dynamo-based tool.
Calibrating the Solar Dynamo: Magnetic Activity Cycles of Southern Sun-like Stars
Concentrating on the 1/4 keV X-ray band, and accounting for the state of the Solar Cycle and the sight line geometries during the ROSAT All Sky Survey, (20) calculated the heliospheric and geocoronal SWCX contributions to the 1/4 keV flux observe d by ROSAT.
Revising the Local Bubble Model due to Solar Wind Charge Exchange X-ray Emission
The firs t technique is largely better at low frequency where acoustic modes are not perturbed by the solar cycle (below 1.6 mHz) and where gravity modes are expected (below 0.4 mHz).
Laboratory performances of the solar multichannel resonant scattering spectrometer prototype of the GOLF-New Generation instrument
Also the relation between those fields and the global solar dynamo can be revealed by spanning the observations over a significant fraction of a solar cycle.
The Prototype of the Small Synoptic Second Solar Spectrum Telescope (S5T)
However, observations by Bianda et al. (2006) clearly show significant variations in several lines of the Second Solar Spectrum with the solar cycle.
The Prototype of the Small Synoptic Second Solar Spectrum Telescope (S5T)
This takes place around the solar cycle minimum.
A solar cycle lost in 1793--1800: Early sunspot observations resolve the old mystery
The damaging particle radiation flux incident on a spacecraft depends on exactly when the mission occurs within the ∼ 11 year solar cycle (Barth et al. 2000).
The effects of charge transfer inefficiency (CTI) on galaxy shape measurements
There is an order of magnitude difference in the flux of solar protons during the heaviest and lightest parts of the solar cycle (see, e.g.
The effects of charge transfer inefficiency (CTI) on galaxy shape measurements
This is a large uncertainty because the radiation flux due to the Sun can vary by an order of magnitude over the solar cycle (Barth et al. 2000).
The effects of charge transfer inefficiency (CTI) on galaxy shape measurements
It is generally believed that the solar cycle corresponds to a hydromagnetic dynamo process operating in some place within the solar interior.
Cosmic Magnetic Fields: from Stars and Galaxies to the Primordial Universe
Measurements of the interplanetary magnetic field (IMF) over several solar cycles do not agree with computed values of open magnetic flux from potential field extrapolations.
A Non-potential Model for the Sun's Open Magnetic Flux
In Figure 1, the grey line shows the observed Bx for Solar Cycle 23, while the three colored lines show PFSS predictions of BE using Equation 1 with different photospheric magnetic field data (Section 2).
A Non-potential Model for the Sun's Open Magnetic Flux
This shortfall has been noted over the past three solar cycles [e.g., Riley , 2007], and several possible explanations have been proposed.
A Non-potential Model for the Sun's Open Magnetic Flux
Comparison of measured radial IMF at 1AU with various PFSS extrapolations over Solar Cycle 23.
A Non-potential Model for the Sun's Open Magnetic Flux
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