Nearby is another bright region named Vinalia Faculae, which is more diffuse in shape and texture, and it appears to have been formed by a somewhat different process.
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Solar faculae are bright spots that form in the canyons between solar granules, short-lived convection cells several thousand kilometers across that constantly form and dissipate over timescales of several minutes. Faculae are produced by concentrations of magnetic field lines. Strong concentrations of faculae appear in solar activity, with or without sunspots. The faculae and the sunspots contribute noticeably to variations in the "Solar constant".
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Faculae have a strong influence on the solar constant, and the more readily detectable (because chromospheric) plage areas traditionally are used to monitor this influence. In this context, "active network" consists of plage- like brightenings extending away from active regions as their magnetism appears to diffuse into the quiet Sun, but constrained to follow the network boundaries. Because we can explain faculae with the strictly photospheric "hot wall" model, the actual physical relationship between plage and faculae is not clear.
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MESSENGER approximate color image Slang Faculae is a bright region on the surface of Mercury, located at 24.5° N, 179.3° W. It was named by the IAU in 2018. Slang is the Afrikaans word for snake. Slang Faculae lies on the southeast rim of the Caloris basin, east of Atget crater and south of March crater.
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Despite the fact that ACRIM I, ACRIM II, ACRIM III, VIRGO and TIM all track degradation with redundant cavities, notable and unexplained differences remain in irradiance and the modeled influences of sunspots and faculae.
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Amalthea (photo by Voyager 1). Lyctos Facula is the lower bright spot Lyctos Facula is a bright mountain on one of Jupiter's smallest moons Amalthea. It is believed to have a width of 25 kilometers . It is one of two named faculae that appear on Amalthea, the other being Ida Facula.
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A plage is a bright region in the chromosphere of the Sun, typically found in regions of the chromosphere near sunspots. The term itself is poetically taken from the French word for "beach". The plage regions map closely to the bright spots (faculae) in the photosphere below, but the latter have much smaller spatial scales. Accordingly, plage occurs most visibly near a sunspot region.
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It has developed a four-year activity cycle. During the period 2000–2004, it showed a strong activity cycle with little correlation between photometric variation and surface activity. This was followed by a flatter activity cycle from 2004–2008 that showed an inverse brightness variation with the level of activity. The difference in the two cycles may indicate a change from faculae-dominated to star spot-dominated variations in luminosity.
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A coronal transient as seen by the SMM on May 5, 1980. Significantly, the SMM's ACRIM instrument package showed that contrary to expectations, the Sun is actually brighter during the sunspot cycle maximum (when the greatest number of dark 'sunspots' appear). This is because sunspots are surrounded by bright features called faculae, which more than cancel the darkening effect of the sunspot. The major scientific findings from the SMM are presented in several review articles in a monograph.
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TSI varies in phase with the solar magnetic activity cycle with an amplitude of about 0.1% around an average value of about 1361.5 W/m2 (the "solar constant"). Variations about the average of up to −0.3% are caused by large sunspot groups and of +0.05% by large faculae and the bright network on a 7-10-day timescale (see TSI variation graphics). Satellite-era TSI variations show small but detectable trends. TSI is higher at solar maximum, even though sunspots are darker (cooler) than the average photosphere.
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This is caused by magnetized structures other than sunspots during solar maxima, such as faculae and active elements of the "bright" network, that are brighter (hotter) than the average photosphere. They collectively overcompensate for the irradiance deficit associated with the cooler, but less numerous sunspots. The primary driver of TSI changes on solar rotational and sunspot cycle timescales is the varying photospheric coverage of these radiatively active solar magnetic structures. Energy changes in UV irradiance involved in production and loss of ozone have atmospheric effects.
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Study was hampered during the 17th century due to the low number of sunspots during what is now recognized as an extended period of low solar activity, known as the Maunder Minimum. By the 19th century, then- sufficient sunspot records allowed researchers to infer periodic cycles in sunspot activity. In 1845, Henry and Alexander observed the Sun with a thermopile and determined that sunspots emitted less radiation than surrounding areas. The emission of higher than average amounts of radiation later were observed from the solar faculae.
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A drawing of a sunspot in the Chronicles of John of Worcester. The Sun's apparent surface, the photosphere, radiates more actively when there are more sunspots. Satellite monitoring of solar luminosity revealed a direct relationship between the Schwabe cycle and luminosity with a peak-to-peak amplitude of about 0.1%. Luminosity decreases by as much as 0.3% on a 10-day timescale when large groups of sunspots rotate across the Earth's view and increase by as much as 0.05% for up to 6 months due to faculae associated with large sunspot groups.
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Cererian faculae were initially speculated to suggest current or past outgassingLPSC 2015: First results from Dawn at Ceres: provisional place names and possible plumes on Ceres, perhaps due to volcanism or cometary activity. The brightest cluster of spots (Cereale Facula) is located in the center of an crater called Occator. These bright features have an albedo of about 40%, four times brighter than the average of Ceres's surface. The spots appear to be mostly sodium carbonate (), implying that hydrothermal activity followed by evaporation of the water is probably what created the spots.
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He likewise drew up a Blue-book on the climate of "The Isle of Desolation", as Kerguelen was called by Captain Cook. In 1882 he went again with Sidgreaves to observe a similar transit in Madagascar,The Transit of Venus: historical observations - work in progress and he again took advantage of the occasion for magnetic purposes. In 1874 he became a Fellow of the Royal Society. At Stonyhurst College, while he greatly developed the meteorological work of the observatory, and in the province of astronomy made frequent observations of Jupiter's satellites, stellar occultations, comets, and meteors, it was in the department of solar physics that he specially laboured, paying particular attention to sun spots and faculae.
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Active regions are ensembles of loop structures connecting points of opposite magnetic polarity in the photosphere, the so-called coronal loops. They generally distribute in two zones of activity, which are parallel to the solar equator. The average temperature is between two and four million kelvin, while the density goes from 109 to 1010 particles per cm3. Illustration depicting solar prominences and sunspots Active regions involve all the phenomena directly linked to the magnetic field, which occur at different heights above the Sun's surface: sunspots and faculae, occur in the photosphere, spicules, Hα filaments and plages in the chromosphere, prominences in the chromosphere and transition region, and flares and coronal mass ejections happen in the corona and chromosphere.
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The Sun's photosphere is around 100 kilometers thick, and is composed of convection cells called granules—cells of plasma each approximately 1000 kilometers in diameter with hot rising plasma in the center and cooler plasma falling in the narrow spaces between them, flowing at velocities of 7 kilometer per second. Each granule has a lifespan of only about twenty minutes, resulting in a continually shifting "boiling" pattern. Grouping the typical granules are super granules up to 30,000 kilometers in diameter with lifespans of up to 24 hours and flow speeds of about 500 meter per second, carrying magnetic field bundles to the edges of the cells. Other magnetically-related phenomena include sunspots and solar faculae dispersed between the granules.
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List of geological features on Mercury is an itemization of mountains, valleys, craters and other landform features of the planet Mercury. Different types of features are named after different things: Mercurian ridges are called dorsa, and are named after astronomers who made detailed studies of the planet; valleys are called valles, and are named after ancient abandoned cities, towns, and settlements; crater chains are called catenae and are named after radio telescope facilities; plains are called planitiae, and most are named after mythological names associated with Mercury; escarpments are called rupes and are named after the ships of famous explorers; long, narrow depressions are called fossae and are named after works of architecture; bright spots are called faculae and are named after the word snake in various languages. See also list of craters on Mercury, list of albedo features on Mercury, and list of quadrangles on Mercury Longitude is west longitude.
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