All articles starting with S
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Solar boat
A solar boat is a watercraft whose electric motor and onboard services run on electricity from photovoltaic panels charging batteries; the first was built in 1881, and MS Tûranor PlanetSolar completed a solar circumnavigation in 2012.
Solar calendar
A solar calendar, or sun calendar, is a calendar whose dates track the Earth's position around the Sun so each year keeps pace with the seasons; the Gregorian calendar is one.
Solar campfires
Solar campfires are small, transient extreme-ultraviolet brightenings in the quiet solar corona, first seen in 2020 by Solar Orbiter and studied as possible contributors to heating the Sun's million-degree corona.
Solar car
A solar car, also called a solar-powered or solar electric car, is an electric vehicle whose photovoltaic cells convert sunlight into electricity stored in batteries.
Solar carport
A solar carport is a canopy structure built over parking spaces with photovoltaic modules mounted on its roof, generating electricity while sheltering vehicles and often hosting EV chargers.
Solar cell
A solar cell, also called a photovoltaic (PV) cell, is a semiconductor device that converts sunlight directly into electricity. The first practical cell was demonstrated at Bell Labs in 1954.
Solar chimney
A solar chimney heats air with sunlight so it rises through a vertical channel, ventilating a building or, at large scale, driving turbines to generate electricity.
Solar combisystem
A solar combisystem is a solar heating installation providing both domestic hot water and space heating, with an auxiliary source such as gas or biomass.
Solar composition
Solar composition is the measured abundance of chemical elements in the Sun, determined from photospheric spectroscopy, CI chondrite meteorites, and Genesis solar wind samples; it serves as the reference for stellar chemistry.
Solar constant
The solar constant is the amount of solar energy per unit area arriving at the top of Earth's atmosphere, measured by satellites as about 1,361 W/m².
Solar cooker
Solar cooker: device cooking food with sunlight alone, first built by Horace de Saussure in 1767. Types include box, panel, parabolic, and heat-storage cookers; standardized cooking power ranges from about 25 W (panel) to 198 W (parabolic).
Solar cooling
Solar cooling is the production of cooling or air conditioning from sunlight, using solar heat to drive a refrigeration cycle or photovoltaic electricity for a conventional chiller.
Solar core
The solar core is the Sun's central region, where nuclear fusion of hydrogen into helium produces about 98% of the Sun's energy at roughly 15,000,000 °C.
Solar corona
The solar corona, also called the Sun's corona, is the outermost layer of the Sun's atmosphere, hotter than the surface below it at over 1 million degrees Celsius.
Solar cycle
The solar cycle, also known as the Schwabe or sunspot cycle, is the roughly 11-year rise and fall of the Sun's magnetic activity, tracked by sunspot numbers.
Solar cycle 25
Solar cycle 25 is the current 11-year cycle of solar activity, the 25th since record-keeping began in 1755, starting at solar minimum in December 2019.
Solar cycle prediction
Solar cycle prediction is the forecasting of the amplitude and timing of an upcoming or ongoing solar cycle, the Sun's roughly 11-year oscillation in magnetic activity.
Solar deity
Solar deity: a god or goddess embodying the Sun or an aspect of it, also called sun god or sun goddess. Found across most recorded cultures, from Ra, Shamash, Helios, and Sol Invictus to Surya and Amaterasu; sun goddesses occur on every continent.
Solar district heating
Solar district heating is the supply of heat from large fields of solar thermal collectors into a district heating network, pioneered in Denmark and now used by 346 towns and cities worldwide.
Solar Dynamics Observatory
The Solar Dynamics Observatory (SDO) is a NASA solar-physics spacecraft launched on February 11, 2010, observing the Sun nearly continuously to understand solar variability and space weather.
Solar dynamo
The solar dynamo is the hydromagnetic process inside the Sun that generates its large-scale magnetic field, driving the 11-year sunspot cycle and the 22-year polarity reversal cycle.
Solar dynasty
The Solar dynasty, or Suryavansha, is the lineage of Hindu tradition tracing royal descent from the sun god Surya, headed by the Ikshvaku dynasty of Kosala, whose capital was Ayodhya.
Solar eclipse
A solar eclipse, or eclipse of the sun, occurs when the Moon passes between the Sun and Earth, obscuring the Sun for viewers in the Moon's shadow.
Solar eclipse of April 8, 2024
The solar eclipse of April 8, 2024, called the Great North American Eclipse, was a total solar eclipse crossing North America with up to 4 minutes 28 seconds of totality.
Solar eclipse of August 11, 1999
The total solar eclipse of August 11, 1999 crossed central Europe, Turkey, the Middle East, and India, and was the last total eclipse of the 20th century.
Solar eclipse of August 12, 2026
A total solar eclipse on August 12, 2026, whose path of totality crossed Greenland, Iceland, and Spain, the first over mainland Spain in over a century.
Solar eclipse of August 12, 2045
The solar eclipse of August 12, 2045 is a total solar eclipse crossing the United States, the Caribbean, and northern South America, with totality lasting over 6 minutes.
Solar eclipse of August 18, 1868
A long total solar eclipse on August 18, 1868, known as the King of Siam's eclipse, during which spectroscopic observation of the Sun led to the discovery of helium.
Solar eclipse of August 21, 1560
The total solar eclipse of August 21, 1560 crossed central Europe and the Iberian Peninsula, observed by Christopher Clavius at Coimbra and remembered for drawing Tycho Brahe to astronomy.
Solar eclipse of August 21, 2017
The total solar eclipse of August 21, 2017, dubbed the Great American Eclipse, crossed the contiguous United States coast to coast, the first since 1918.