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'''Sunspots''' are areas seen as dark spots on the [[photosphere]] of the [[Sun]].<ref name=britannica>[https://www.britannica.com/topic/sunspot Sunspot] from britannica.com</ref> Sunspots are concentrations of [[magnetic field|magnetic flux]], typically occurring in bipolar clusters or groups and are temporary features lasting anywhere from a few of hours to several months. They appear dark because are much cooler than the surrounding photosphere with temperatures of around 3,800 K compared to the rest of the photosphere's 5,800 K.<ref name=coolcosmos>[http://coolcosmos.ipac.caltech.edu/ask/13-Why-are-sunspots-darker-than-the-rest-of-the-Sun- Why are sunspots darker than the rest of the Sun?] from coolcosmos.ipac.caltech.edu</ref> Because the Sun radiates as a [[black body]], this results in sunspots appearing dimmer compared to the rest of the surface. The opposite of a sunspot is a '''facula''' (plural: faculae), a circular to subcircular region which is brighter than the surrounding area. Sunspots are classified based on their size and complexity by the modified Zurich scale.<ref name=britannica/> Similar spots have also been oberved on other [[star]]s where they are called "starspots."

'''Sunspots''' are areas seen as dark spots on the [[photosphere]] of the [[Sun]].<ref name=britannica>[https://www.britannica.com/topic/sunspot Sunspot] from britannica.com</ref> Sunspots are concentrations of [[magnetic field|magnetic flux]], typically occurring in bipolar clusters or groups and are temporary features lasting anywhere from a few of hours to several months. They appear dark because are much cooler than the surrounding photosphere with temperatures of around 3,800 K compared to the rest of the photosphere's 5,800 K.<ref name=coolcosmos>[http://coolcosmos.ipac.caltech.edu/ask/13-Why-are-sunspots-darker-than-the-rest-of-the-Sun- Why are sunspots darker than the rest of the Sun?] from coolcosmos.ipac.caltech.edu</ref> Because the Sun radiates as a [[black body]], this results in sunspots appearing dimmer compared to the rest of the surface. The opposite of a sunspot is a '''facula''' (plural: faculae), a circular to subcircular region which is brighter than the surrounding area. Sunspots are classified based on their size and complexity by the modified Zurich scale.<ref name=britannica/> Similar spots have also been oberved on other [[star]]s where they are called "starspots."

Sunspots tend to be quite varied in their properties, some can be several times the size of the [[Earth]] while others are so small they are at the limit of telescopic observation.<ref name=britannica/> They are normally composed of a dark central region, the umbra, enclosed by a lighter region known as the penumbra. Sunspots are most often found in pairs or groups, with one following the other as they rotate around the Sun due to them having opposite polarity (i.e. one sunspot is the equivalent of the North pole of a [[magnet]] and the other is the South pole.) With each sunspot cycle, the polarity of the leading spot flips. However it is possible for isolated sunspots to form.  

Sunspots tend to be quite varied in their properties, some can be several times the size of the [[Earth]] while others are so small they are at the limit of telescopic observation.<ref name=britannica/> They are normally composed of a dark central region, the umbra, enclosed by a lighter region known as the penumbra. Sunspots are most often found in pairs or groups, with one following the other as they rotate around the Sun due to them having opposite polarity (i.e. one sunspot is the equivalent of the North pole of a [[magnet]] and the other is the South pole.) With each sunspot cycle, the polarity of the leading spot flips. However it is possible for isolated sunspots to form.  

Sunspots are cooler than the surrounding [[photosphere]], with temperatures of 3,800 K the norm.<ref name=coolcosmos/> This is only true however in optical light. When pictured in other [[electromagnetic spectrum|wavelengths]] such as [[ultraviolet]] or [[x-ray]]s, they appear much brighter than their surroundings.<ref name=noaa>[https://www.swpc.noaa.gov/phenomena/sunspotssolar-cycle Sunspots/Solar cycle] from swpc.noaa.gov</ref> Their [[magnetic field]] is generally 2,000-4,000 Gauss, a couple of thousand greater than that of the Earth.<ref name=britannica/> This traps very hot (around 1 million K) gas above the sunspot in the form of a [[plasma]].<ref name=noaa/> The gas can often be seen in forming spectacular rings as it traces out magnetic field lines. As this plasma is much hotter that the rest of the Sun's surface, it radiates with a much shorter wavelength meaning it is dominant in the ultraviolet and x-ray portions of its [[electromagnetic spectrum|spectrum]].

Sunspots are cooler than the surrounding [[photosphere]], with temperatures of 3,800 K the norm.<ref name=coolcosmos/> This is only true however in optical light. When pictured in other [[electromagnetic spectrum|wavelengths]] such as [[ultraviolet]] or [[x-ray]]s, they appear much brighter than their surroundings.<ref name=noaa>[https://www.swpc.noaa.gov/phenomena/sunspotssolar-cycle Sunspots/Solar cycle] from swpc.noaa.gov</ref> Their [[magnetic field]] is generally 2,000-4,000 Gauss, a couple of thousand greater than that of the Earth.<ref name=britannica/> This traps very hot (around 1 million K) gas above the sunspot in the form of a [[plasma]].<ref name=noaa/> The gas can often be seen in forming spectacular rings as it traces out magnetic field lines. As this plasma is much hotter that the rest of the Sun's surface, it radiates with a much shorter wavelength meaning it is dominant in the ultraviolet and x-ray portions of its [[electromagnetic spectrum|spectrum]].