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Solar Cycle 24
Solar cycle 24 is the most recently completed solar cycle, the 24th since 1755, when extensive recording of solar sunspot activity began.Kane, R.P. (2002).Some Implications Using the Group Sunspot Number Reconstruction. ''Solar Physics'' 205(2), 383-401. It began in December 2008 with a minimum smoothed sunspot number of 2.2, and ended in December 2019. Activity was minimal until early 2010. It reached its maximum in April 2014 with a 23 months smoothed sunspot number of 81.8. This maximum value was substantially lower than other recent solar cycles, down to a level which had not been seen since cycles 12 to 15 (1878-1923). Predictions Prior to the minimum between the end of Solar Cycle 23 and the beginning of Solar Cycle 24, two theories predicted how strong Solar Cycle 24 would be. One camp postulated that the Sun retained a long memory (Solar Cycle 24 would be active) while the other asserted that it had a short memory (quiet). Prior to 2006, the difference was substantial ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Solar Cycle 23
Solar cycle 23 was the 23rd solar cycle since 1755, when extensive recording of solar sunspot activity began. The solar cycle lasted 12.3 years, beginning in August 1996 and ending in December 2008. The maximum smoothed sunspot number observed during the solar cycle was 180.3 (November 2001), and the starting minimum was 11.2. During the minimum transit from solar cycle 23 to 24, there were a total of 817 days with no sunspots. Compared to the last several solar cycles, it was fairly average in terms of activity. History Large solar flares and coronal mass ejections (CMEs) occurred on 7 September 2005 (X17), 15 April 2001 (X14.4) and 29 October 2003 (X10), with auroras visible in mid-latitudes. 2000 One of the first major aurora displays of solar cycle 23 occurred on 6 April 2000, with bright red auroras visible as far south as Florida and South Europe. On 14 July 2000, the CME hurled by a X5.7 solar flare provoked an extreme (G5 level) geomagnetic storm the next day. Know ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Earth's Magnetic Field
Earth's magnetic field, also known as the geomagnetic field, is the magnetic field that extends from Earth's interior out into space, where it interacts with the solar wind, a stream of charged particles emanating from the Sun. The magnetic field is generated by electric currents due to the motion of convection currents of a mixture of molten iron and nickel in Earth's outer core: these convection currents are caused by heat escaping from the core, a natural process called a geodynamo. The magnitude of Earth's magnetic field at its surface ranges from . As an approximation, it is represented by a field of a magnetic dipole currently tilted at an angle of about 11° with respect to Earth's rotational axis, as if there were an enormous bar magnet placed at that angle through the center of Earth. The North geomagnetic pole actually represents the South pole of Earth's magnetic field, and conversely the South geomagnetic pole corresponds to the north pole of Earth's magneti ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Spörer's Law
Spörer's law predicts the variation of sunspot latitudes during a solar cycle. It was discovered by the English astronomer Richard Christopher Carrington around 1861. Carrington's work was refined by the German astronomer Gustav Spörer. At the start of a sunspot cycle, sunspots tend to appear around 30° to 45° latitude on the Sun's surface. As the cycle progresses, sunspots appear at lower and lower latitudes, until they average 15° at solar maximum. The average latitude of sunspots then continues to drift lower, down to about 7° and then while the old sunspot cycle fades, sunspots of the new cycle start appearing at high latitudes. See also * Solar variation * Wolf number * Joy's law (astronomy) In astronomy, Joy's law describes the distribution of sunspots in active region An active region is a temporary region in the Sun's atmosphere characterized by a strong and complex magnetic field. They are often associated with sunspots and are ... References Solar pheno ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hale's Law
In solar physics, Hale's law, also known as Hale's polarity law or the Hale–Nicholson law, describes the tendency for bipolar active regions within the same northern or southern hemisphere to have the same leading magnetic polarity with respect to the solar rotation, and for those in the opposite hemisphere to have the opposite leading polarity. It further describes how this pattern reverses from one sunspot cycle to the next. It is named after George Ellery Hale and Seth Barnes Nicholson. Hale's law, along with Joy's law (astronomy), Joy's law, provides observational evidence for the solar dynamo. History The solar magnetic field was first detected in 1909 by George Ellery Hale when he showed observationally that sunspots had strong, bipolar magnetic fields. With these observations, Hale also noted how the majority of sunspot groups within the same northern or southern hemisphere shared the same leading polarity and that this pattern reversed across the equator. As solar cycl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sunspot 10981 Solar Cycle 24
Sunspots are phenomena on the Sun's photosphere that appear as temporary spots that are darker than the surrounding areas. They are regions of reduced surface temperature caused by concentrations of magnetic flux that inhibit convection. Sunspots appear within active regions, usually in pairs of opposite magnetic polarity. Their number varies according to the approximately 11-year solar cycle. Individual sunspots or groups of sunspots may last anywhere from a few days to a few months, but eventually decay. Sunspots expand and contract as they move across the surface of the Sun, with diameters ranging from to . Larger sunspots can be visible from Earth without the aid of a telescope. They may travel at relative speeds, or proper motions, of a few hundred meters per second when they first emerge. Indicating intense magnetic activity, sunspots accompany other active region phenomena such as coronal loops, prominences, and reconnection events. Most solar flares and corona ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
NOAA
The National Oceanic and Atmospheric Administration (abbreviated as NOAA ) is an United States scientific and regulatory agency within the United States Department of Commerce that forecasts weather, monitors oceanic and atmospheric conditions, charts the seas, conducts deep sea exploration, and manages fishing and protection of marine mammals and endangered species in the U.S. exclusive economic zone. Purpose and function NOAA's specific roles include: * ''Supplying Environmental Information Products''. NOAA supplies to its customers and partners information pertaining to the state of the oceans and the atmosphere, such as weather warnings and forecasts via the National Weather Service. NOAA's information services extend as well to climate, ecosystems, and commerce. * ''Providing Environmental Stewardship Services''. NOAA is a steward of U.S. coastal and marine environments. In coordination with federal, state, local, tribal and international authorities, NOAA manages the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Coronal Mass Ejection
A coronal mass ejection (CME) is a significant release of plasma and accompanying magnetic field from the Sun's corona into the heliosphere. CMEs are often associated with solar flares and other forms of solar activity, but a broadly accepted theoretical understanding of these relationships has not been established. If a CME enters interplanetary space, it is referred to as an interplanetary coronal mass ejection (ICME). ICMEs are capable of reaching and colliding with Earth's magnetosphere, where they can cause geomagnetic storms, aurorae, and in rare cases damage to electrical power grids. The largest recorded geomagnetic perturbation, resulting presumably from a CME, was the solar storm of 1859. Also known as the Carrington Event, it disabled parts of the at the time newly created United States telegraph network, starting fires and shocking some telegraph operators. Near solar maxima, the Sun produces about three CMEs every day, whereas near solar minima, there is abou ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Space Weather
Space weather is a branch of space physics and aeronomy, or heliophysics, concerned with the time varying conditions within the Solar System, including the solar wind, emphasizing the space surrounding the Earth, including conditions in the magnetosphere, ionosphere, thermosphere, and exosphere. Space weather is distinct from, but conceptually related to, the terrestrial weather of the atmosphere of Earth ( troposphere and stratosphere). The term "space weather" was first used in the 1950s and came into common usage in the 1990s. Later, it was generalized to a " space climate" research discipline, which focuses on general behaviors of longer and larger-scale variabilities and effects. History For many centuries, the effects of space weather were noticed, but not understood. Displays of auroral light have long been observed at high latitudes. Genesis In 1724, George Graham reported that the needle of a magnetic compass was regularly deflected from magnetic north o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Quadrupole
A quadrupole or quadrapole is one of a sequence of configurations of things like electric charge or current, or gravitational mass that can exist in ideal form, but it is usually just part of a multipole expansion of a more complex structure reflecting various orders of complexity. Mathematical definition The quadrupole moment tensor ''Q'' is a rank-two tensor—3×3 matrix. There are several definitions, but it is normally stated in the traceless form (i.e. Q_ + Q_ + Q_ = 0). The quadrupole moment tensor has thus nine components, but because of transposition symmetry and zero-trace property, in this form only five of these are independent. For a discrete system of \ell point charges or masses in the case of a gravitational quadrupole, each with charge q_\ell, or mass m_\ell, and position \vec_\ell = \left(r_, r_, r_\right) relative to the coordinate system origin, the components of the ''Q'' matrix are defined by: : Q_ = \sum_\ell q_\ell\left(3r_ r_ - \left\, \vec_\ell \rig ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
National Astronomical Observatory Of Japan
The (NAOJ) is an astronomical research organisation comprising several facilities in Japan, as well as an observatory in Hawaii and Chile. It was established in 1988 as an amalgamation of three existing research organizations - the Tokyo Astronomical Observatory of the University of Tokyo, International Latitude Observatory of Mizusawa, and a part of Research Institute of Atmospherics of Nagoya University. In the 2004 reform of national research organizations, NAOJ became a division of the National Institutes of Natural Sciences. Facilities ;Mitaka Campus ( Mitaka, Tokyo. ) :The Headquarters, Astronomy Data Center, Advanced Technology Center, Public Relations Center :Solar Flare Telescope, Sunspot Telescope, TAMA 300 gravitational wave detector :Tokyo Photoelectric Meridian Circle :Historical instruments: Solar Tower Telescope, 65cm refractor dome, 20cm refractor dome ;Nobeyama Radio Observatory (Minamimaki, Nagano, ) :45m Millimeter Radio Telescope, Nobeyama Radio P ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Big Think
Big Think is a multimedia web portal founded in 2007 by Victoria Brown and Peter Hopkins. The website is a collection of interviews, presentations, and round table discussions with experts from a wide range of fields. Victoria Brown is the acting CEO and Peter Hopkins is the acting president of the company. History The company was founded when Brown and Hopkins met while working with Google Video to digitize the VHS archives of The Charlie Rose Show in 2006. They began contemplating how to organize information into "short-form intellectual videos targeting online audiences" and envisioned "an online platform where the world’s leading experts could weigh in on current issues". In 2008 they launched with only video content. The materials involve short clips but with enough content so that they foster thinking, learning, and debate. In 2009, they branched into blogs and written content. Their first notable blogger was Michio Kaku. Other personalities include Angelina Jolie, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Solar Storm Of 1859
The Carrington Event was the most intense geomagnetic storm in recorded history, peaking from 1 to 2 September 1859 during solar cycle 10. It created strong auroral displays that were reported globally and caused sparking and even fires in multiple telegraph stations. The geomagnetic storm was most likely the result of a coronal mass ejection (CME) from the Sun colliding with Earth's magnetosphere. The geomagnetic storm was associated with a very bright solar flare on 1 September 1859. It was observed and recorded independently by British astronomers Richard Christopher Carrington and Richard Hodgson—the first records of a solar flare. A geomagnetic storm of this magnitude occurring today would cause widespread electrical disruptions, blackouts, and damage due to extended outages of the electrical power grid. History The Carrington Event took place a few months before the solar maximum, a period of elevated solar activity, of solar cycle 10. Geomagnetic storm On ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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