Sunspots are cool, dark patches on the Sun's surface. They are caused by disturbances in the sun's magnetic field which make the sunspot about 2700°F (1500°C) cooler than the surrounding area. Sunspots occur where the sun's magnetic field loops up out of the solar surface. The number of sunspots follows an 11-year solar cycle; the current cycle had already peaked in late March 2001 where there was a really big solar flare. Sunspots are visible from Earth. (WARNING: do NOT look at the sun; it can damage your eyes permanently!)
These are temporary areas of magnetic field concentration on the Sun's photosphere (the visible surface of the Sun). In these areas the magnetic concentration prevents the heat from the core of the Sun escaping to the surface, which results in the area being cooler. This is why these areas appear darker in the images.
Temporary magnetic disturbances in the photosphere. They appear dark because temperatures are considerably lower than in surrounding areas. More about sunspots...
When the Sun is viewed through a solar telescope dark spots can be observed on the surface. These are called sunspots. They appear dark to the eye because they are cooler than the surrounding gas although they are still quite hot
Areas of concentrated magnetic feilds on the surface of the sun near its equator. These areas are cooler and, thus appear as darker regions as seen from Earth. The number of these storms fluctuate and reach a peak every 11 years. These variations cause an increase of the solar wind, an array of particles ejected from the Sun, which interfere with radio wave transmissions. (See Pinhole Camera Observatory)
areas of slightly cooler gas that appear on the photosphere as dark areas and are caused by magnetic field lines extending out of or into the Sun
Relatively cooler areas on the sun's surfaces. They represent regions of extremely high magnetic field.
Cooler (and thus darker) regions on the sun where the magnetic field loops up and out of the solar surface.
Dark regions on the Sun which are the centers of large vortices and possess powerful magnetic fields. Maximum sunspot activity occurs in cycles with a period of about 11 years.
cool, dark spots on the sun that result from magnetic storms.
Sunspots are cool, dark patches on the Sun's surface. They are caused by disturbances in the sun's magnetic field which make the sunspot about 2700°F (1500°C) cooler than the surrounding area. Sunspots occur where the sun's magnetic field loops up out of the solar surface. The number of sunspots follows an 11-year cycle; the current cycle will peak in the middle of 2000. Sunspots are visible from Earth. (WARNING: do NOT look at the sun; it can damage your eyes permanently!) The sunspot cycle was discovered by H. Schwabe in 1843.
These appear as dark patches on the photosphere. The larger spots have a darker central region (the umbra) surrounded by a lighter outer region (the penumbra). Sunspots are cooler than the photosphere with the umbral regions being about 2000°C cooler and the penumbra about 500°C cooler. Individual spots can range in diameter from 1000 km to 100,000 km (the Earth has a diameter of 12750 km). Sunspots are linked to the surface magnetic field of the Sun.
Dark, irregular areas on the solar surface with strong magnetic fields (1000 to 2000 Gauss) surrounded by gray zones (penumbra). Sunspots occur mostly in pairs, with opposite magnetic polarity; they persist for periods of days, weeks, or months. Their temperatures are about 2000 K lower than the temperature of the surrounding photosphere (5780° K). The frequency of sunspots follows an eleven - year cycle.
dark, relatively cool areas on the surface of the sun
Relatively dark spots on the sun that contain intense magnetic fields. The sunspot activity on the sun is not constant and varies on short times scales (day to day). There is also an 11-year sunspot cycle where the amount of sunspots visible on the sun varies. Sunspots are easily visible on the images we get using our heliostat solar telescope.