Antumbra
The
antumbra is the section of a
shadow where an
annular eclipse may be viewed.
In an annular eclipse, the
moon is not of sufficient size to completely cover the
sun, and so its shadow is not long enough to reach the
Earth and result in a total
solar eclipse. At maximum eclipse, the moon is surrounded by a ring, or
annulus, of light, and the location on Earth where the ring can be seen is also the location of the antumbra.
Although the antumbra may be referred to as a "negative shadow", it is nevertheless darker than the
penumbra, just like the
umbra is in a
total eclipse. However, whereas the umbra is completely devoid of sunlight, the antumbra is not because of the remaining ring.
*
umbra*
penumbra
