Solar eclipses
The most magnificent solar phenomenon we may experience from the ground is total solar eclipses – and they are due not to the Sun – but the moon.
Solar eclipses are due to the fact that the moon covers or shadows the Sun in such a way that the entire part of the Sun disk is darkened.
Eclipses are rather rare. People often travel half the globe in order to experience the most magnificent of all eclipses – total solar eclipses. |
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| Lunar orbit. |
| The moon travels round the Earth in well over 27 days. Once every twenty-seven days, at new moon, the moon gets fairly close to the Sun in the sky. Why do we not get solar eclipses every twenty-seven days? |
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| How often do eclipses occur? |
| Each year there are maximum 5 and minimum 2 solar eclipses on the Earth. Most of them are partial, i.e. the moon does not shadow the Sun at any place on the globe. Then the moon passes either somewhat above or somewhat below the Sun in the sky. |
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| Total solar eclipse |
| It is a rather exceptional experience to witness a total solar eclipse! If the weather is fine, the following happens: Using safe equipment we see that the moon is only just beginning to glide across the Sun’s disc. |
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| Importance for scientific research |
| Right up to the space age the total solar eclipses gave us the only opportunities of observing the outer atmosphere of the Sun. Researchers from all over the world pilgrimaged with their instruments in order to exploit the few minutes the eclipses lasted. |
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| Partial and ring-shaped solar eclipses |
| Partial, or gradual eclipses occur far more frequently than the total ones and are visible across far larger areas. |
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