Welcome everyone to universe evolution.well this a compulsory site one(universe lovers) has to look through.. i'll be posting some thrilling,mysterious facts about our solar system...
WHY DOES THE SUN HAVE SPOTS?
Unlike earth, the sun has an extremely complicated magnetic field.A large part of this magnetic field runs beneath the surface of the sun in the form of so - called "magnetic tubes".Sometimes these tubes can break through the sun's surface, and where they do so,strong magnetic fields prevent hot matters from rising out of the sun's interior,cooling the affected areas of the surface to a temperature of 4000^o c. Because of their lower temperature, these regions aren't bright as the rest of the sun - which is about 1500^o c hotter - & thus they appear as dark spots on the sun's surface.Sunspots are between 2500 km and 50000 km wide, which means they can be several times larger than earth.The life span of individual sunspots varies from days to months.
DOES THE SUN ALWAYS HAVE THE SAME NO OF SUNSPOTS?
Sunspots numbers rise and fall in a cycle of approximately 11 years. The last sunspot maximum was in 2000,so the next one is expected in 2011.The sunspot cycle is controlled by the sun's magnetic field,which changes direction every 11 years.
DO OTHER STAR'S ALSO HAVE SPOTS?
Our sun is definitely not exceptional,and other stars also have dark spots in number's that fluctuate in accordance with a regular cycle.The magnetic processes at work appear to be very similar. These 'starspots' can be even larger than the spots on our sun.