glimpse v. n.
a look at sb/sth for a very short time, when you do not see the person or thing completely
corridor n.
a long narrow passage
Why:
- Solar eclipses happen when the Moon blocks the light from the Sun.
- A solar eclipse occurs when the Sun, the Moon and the Earth all line up. The Moon blocks the light of the Sun, and casts a shadow on the Earth.
Phenomena:
- During a total solar eclipse, the sky appears as dark as night, and you can see the Sun's glowing corona(a ring of light seen around the sun or moon, especially during an eclipse).
- Partial
- Total
- Annular: If the Moon is further away from the Earth than normal, then it will not appear large enough in the sky to cover the Sun. The Sun appears as a ring with a dark centre.
- Hybrid: A hybrid eclipse is one which appears as a total eclipse in some parts of the world, and as an annular eclipse in others.
Why don't you see a solar eclipse every month?
The Moon goes around the Earth once every four weeks. However, it revolves(revolve: to go in a circle around a central point) at an angle to Earth's path around the Sun. So the Earth, Moon and Sun do not end up in a straight line every month.
Why do we not see an eclipse when other objects pass in front of the Sun?
Like the Moon, the planets Mercury and Venus also pass between the Earth and the Sun from time to time. However, they are much further away from the Earth than the Moon. They look much smaller in the sky, and never block the light of the Sun completely.
In fact, it is an unlikely coincidence that we see total solar eclipses at all. The Moon is about 400 times smaller than the Sun, but also happens to be about 400 times closer. Therefore, the two bodies look about the same size in the sky.
The Moon is moving slowly away from the Earth (at a rate of a couple of centimetres a year.) In a billion years' time, the Moon will appear too small for there to be any total solar eclipses at all.
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