cycle is known as solar minimum. ⢠The energy that sunspots lack in heat is made up instead by the energy of the magne
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GEOGRAPHY SUNSPOTS
• Sunspots are darker, cooler areas on the surface of the sun in a region called the photosphere. The photosphere has a temperature of 5,800 degrees Kelvin. Sunspots have temperatures of about 3,800 degrees K. • Though sunspots appear darker than the rest of the sun to the naked eye, when these active regions are examined in ultraviolet or x-rays wavelengths, then sunspots and the associated active regions appear considerably brighter than the other areas of the Sun. • They are caused by interactions with the Sun's magnetic field. • Sunspots occur over regions of intense magnetic activity, and when that energy is released, it results in solar flares and solar winds. • The total number of sunspots with an 11-year period known as the solar cycle. The peak of the solar cycle is known as solar maximum and the valley of the cycle is known as solar minimum. • The energy that sunspots lack in heat is made up instead by the energy of the magnetic field. Changes in these magnetic fields are the main source of most of space weather, like solar flares (Radio Blackouts) and fast coronal mass ejections (CMEs). • A solar flare is a sudden release of energy from the sun, while a CME actually shoots hot plasma from the sun into space.
PHOTOSPHERE Photosphere is the visible surface of Sun where temperature is around 5500°C. This part gives us light, which takes around 8 minutes to reach from sun to earth. CHROMOSPHERE Chromosphere is a thin layer of gas above the photosphere. Along with Corona, it makes the atmosphere of Sun. CORONA Corona is a thick layer of gas above chromosphere. It extends millions of kilometres around the sun. Corona and Chromosphere are visible during a total solar eclipse when the sun’s surface is completely hidden behind moon. We note here that Corona is much dimmer than the rest of the Sun, and can only be seen when the Sun is blocked from view-either by a scientific instrument called a coronagraph, or naturally during a solar eclipse.
