Approximately once every 18 months (on average) a total solar eclipse is visible from some place on the Earth's surface. That's two totalities for every three years.
Total solar eclipses are much less frequent because it is much more likely that part of a planet/moon/satellite gets partly in our way of the sun than a planet/moon/satellite gets 100% in our way.
Yes, these are called partial eclipses.
C
'C' (the missing one) is the correct choice.
The corona during total solar eclipses.
About two per year, since the Moon formed. So, around 4000 solar eclipses (and 4000 lunar eclipses) since the year 1. You can check the list of all eclipses since the year 2000 BC on the NASA Eclipse Web Page at the link below.
Alan D. Fiala has written: 'Total solar eclipse of 11 June 1983' -- subject(s): Solar eclipses 'Total solar eclipse of 23 October 1976' -- subject(s): Solar eclipses 'Determination of the mass of Jupiter from a study of the motion of 57 mnemosyne' -- subject(s): Mass 'Total solar eclipse of 31 July 1981' -- subject(s): Solar eclipses 'Solar eclipses of 1977' -- subject(s): Solar eclipses
Actually solar eclipses are slightly more common, but a solar eclipse, and especially the total phase, can only be seen in a relatively narrow strip of Earth.
Five is the theoretical maximum number of solar eclipses in one calendar year; generally 4 partial eclipses and one total or annular eclipse. This configuration happens about every 200 years or so. Interestingly, there will be four solar eclipses in 2011; all will be partial eclipses, visible (if at all) only from polar regions. The last time there were five solar eclipses in a year was in 1935; the next time will be in 2206.
Globally, solar eclipses are slightly more frequent. But a lunar eclipse can be seen from any place where the Moon is above the horizon, whereas a solar eclipse can only be seen from a narrow strip of land. So, for any particular fixed observer, solar eclipses - and especially total solar eclipses - are quite rare. During the 100 years of the 20th Century, there were 228 solar eclipses and 229 lunar ones. So over the long term, you can figure on equal numbers, at the rate of around 7 of each every 3 years.
About twice a year.
On earth there are 2 eclipses, Lunar and Solar eclipses