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As mentioned on the NASA eclipse website the eclipse on the 3rd of November 2013 will be a "Hybrid" eclipse.

I have looked at the diagram on that page but can't see what is different about the eclipse that would explain the word hybrid. This terminology also confuses me:

It is one of the rare hybrid or annular/total eclipses in which some sections of the path are annular while other parts are total.

enter image description here

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A hybrid eclipse is one in which it is a total eclipse in some places and an annular eclipse is seen in other places.

As you may know, a total eclipse is one in which the moon completely covers the disc of the Sun; this allows the solar corona to be seen. Usually the central disc of the Sun is so bright that the corona cannot be seen. An annular eclipse is one in which the Moon is not quite "large" enough to completely block out the Sun - instead, a ring of the Sun's central disc can be seen around the Moon. This ring is too bright for the corona to be seen. Photos of both eclipse types appear below.

Annular Eclipse (credit: Fred Espenak at www.mreclipse.com): Annular eclipse photo

Total Eclipse (credit: Fred Espenak at www.mreclipse.com): enter image description here

The type of eclipse is determined by the geometry of the Sun, Earth, and Moon. Since the Sun and Moon are not constantly at the same distance from the Earth, their apparent sizes will differ. When the Moon is closer to the Earth it appears larger, and when the Sun is farther away it will appear smaller. For this particular eclipse, the geometry is such that the western part of the eclipse's center line will see an annular eclipse, but the rest will have a total eclipse.

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    $\begingroup$ This image shows you just how much the diameter of the moon can vary between perigee (closest approach to Earth) and apogee (furthest from Earth). The moon's orbital eccentricity varies (it has a really complex orbit) - so its apogee and perigee are not usually quite as extreme as in the linked image. $\endgroup$
    – Moriarty
    Commented Nov 3, 2013 at 3:58
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    $\begingroup$ It's still quite amazing that the "apparent" diameters of each body are so close in size (between regular apogee and perigee) as to allow "hybrid" eclipses to occur at all. Amazing to me anyway... $\endgroup$
    – user22542
    Commented Apr 10, 2022 at 19:04
  • $\begingroup$ It is the focal phenomenon where the light/shadow from the sun/moon is so precisely focused on the earth that the eclipse path switches between "annularity" and "totality" as it moves along the ground. The apparent sizes of the sun and moon are so nearly the same that Hybrid eclipses tend to be very brief (i.e. short) when they occur. $\endgroup$
    – user22542
    Commented Jan 23 at 13:19

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