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solar eclipse

In solar eclipse
In a partial eclipse, the centre of the Moon’s disk does not pass across the centre of the Sun’s. After the first contact, the visible crescent of the Sun decreases in width until the centres of the two disks reach their closest approach. This is the moment…
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In eclipse: Eclipses of the Sun
…the eclipse is then called partial for that observer. The umbral cone is narrow at the distance of Earth, and a total eclipse is observable only within the narrow strip of land or sea over which the umbra passes. A partial eclipse may be seen from places within the large…
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geometry of a lunar eclipse

geometry of a total solar eclipse

What happens during a solar eclipse?

How do solar and lunar eclipses occur?

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Solar Eclipse, Eclipse, Solar Flare, Outer Space, Astronomy

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penumbra, (from Latin paene, “almost”; umbra, “shadow”), in astronomy, the outer part of a conical shadow cast by a celestial body, in which the light from the source is partially blocked—as compared to the umbra (q.v.), the shadow’s darkest, central part, where the light is totally excluded. During an eclipse of the Sun, an observer in the penumbra sees the Sun partially obscured. The term also is used for the outer annulus of a sunspot. See also eclipse; solar eclipse; lunar eclipse.