Generally speaking, an eclipse occurs when a celestial body is interposed so that at least a portion of its light is obscured for a period of time. This happens due to a special alignment of the Sun and Moon, which only occurs in certain months and not others. Eclipses are actually quite common, and several happen each year. However, each eclipse is not visible from every location on Earth, so many years can go by where no eclipses can be seen from a particular place.
A solar eclipse happens when the Moon moves into alignment between the Earth and the Sun, so that the view of the Sun is obscured for a time. The shadow of the Moon passes over the surface of the Earth, and eclipse watchers on the ground are able to observe the Moon blocking at least a portion of the Sun’s light.
A lunar eclipse occurs when the Moon is on the opposite side of the Earth from the Sun. The Moon passes through the shadow of the Earth, and eclipse watchers are able to observe a darkening of the Moon, as the Sun’s light shining on the Moon is blocked by the Earth. Some total lunar eclipses can be very dark, where only a smoky, charcoal-grey light can be seen on the Moon’s surface. Some eclipses have a rusty red color, while others are a bright shade of orange, barely darkened at all.
Though the Sun’s direct light is blocked, the Moon is still illuminated by sunlight filtered through the Earth’s atmosphere. The brightness and color of a lunar eclipse corresponds to the amount of dirt in the Earth’s atmosphere, where more atmospheric dirt corresponds with a darker eclipse. The Danjon scale is used to gauge the color and brightness of the Moon during a total lunar eclipse, on a scale where D0 is the darkest and D4 is the brightest.
A total lunar eclipse can appear eerie and mysterious, and is always a very impressive, awe-inspiring sight. However, the sight of a mere lunar eclipse does not come close to comparing to the majestic spectacle of a total eclipse of the Sun!
A total solar eclipse is widely regarded as the most spectacular, fantastical, utterly amazing natural wonder that can be witnessed on Planet Earth! During a total solar eclipse, the brightly blazing Sun is extinguished for several minutes, as the body of the Moon blocks the brilliant rays of daytime. The radiance of the sky plummets, as the brightness of noon is turned into the darkness of midnight, and stars come out in the middle of the day!
A total eclipse of the Sun is widely regarded as a jaw-dropping, gut-level, visceral experience by veteran eclipse observers. Different people have different reactions to this incredible sight. Some people have been known to weep or scream at the sight of the Sun being extinguished by the Moon. Others report standing awestruck, in silence, words failing them.
Everyone who has seen a total eclipse of the Sun agrees that it is like no other sight that can be seen, an alien, otherworldly experience. It’s agreed that no picture, no video, no image or depiction, no Hollywood CG special effect, can come close to capturing the awe and wonder of a total eclipse of the Sun! And it’s coming to the USA in 2017, for the first time in a generation!
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Continue reading about what you can expect to see before, during and after a total eclipse of the Sun at our Total Solar Eclipse Phenomena page.
To learn more about why eclipses occur, and what’s happening with the orbit of the Moon, visit our Celestial Causes of Eclipses page.