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NASA explains how a 'ring of fire' annular solar eclipse occurs and how it differs from a total solar eclipse.

WARNING: People should always use protective solar eclipse eyewear when viewing a solar eclipse.

Credit: NASA Goddard Space Flight Center
Transcript
00:00Roughly every year or two, somewhere in the world, the sun appears for a few moments as a ring of fire in the sky.
00:08This is called an annular solar eclipse.
00:11Annular comes from the Latin word annulus, which means ring.
00:15An annular solar eclipse occurs when a new moon passes directly in front of the sun but appears too small to cover it completely.
00:23But why is that?
00:24It's because the moon's orbit around Earth isn't a perfect circle, but rather an ellipse, or slightly oval-shaped.
00:31This causes the moon to move closer to us and then farther away during its month-long orbit.
00:36When the moon is at its closest point, called perigee, it appears slightly larger in our sky.
00:42When it's farthest from us, at apogee, it appears a little smaller.
00:47But we don't see an annular eclipse every month.
00:51That's because the moon's orbit is also slightly tilted in relation to Earth's orbit around the sun.
00:57This means during most months the moon is either too high or too low to block the sun.
01:02So only when a new moon is at apogee and passes directly between Earth and the sun
01:07do spectators on Earth get the rare opportunity to see the ring of fire in the sky.
01:13Unlike a total solar eclipse, when the moon completely covers the sun,
01:17during an annular eclipse, the sun never fully disappears.
01:21So if you're lucky enough to be in the path of an annular solar eclipse,
01:25make sure to wear your solar eclipse glasses or use other safe solar filters
01:29to witness this spectacular ring of fire in the sky.

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