A total lunar eclipse is one of Nature’s grandest spectacles in which we see the Moon moving through the huge shadow cast by our planet out into space. It begins at 10:28 p.m. EDT on Sunday evening, May 15th as the Moon first enters the shadow and continues until it is fully immersed. Totality begins at 11:29 p.m. and ends at 12:54 a.m. Our satellite then begins to leave the umbra, finally exiting it at 1:55 and ending the eclipse. The eastern half of the country will see the entire event but the eclipse will already be under way as the Moon rises for the western half, depending exactly where you located.
There are several things to notice during the eclipse. One is that the Earth’s shadow is curved as it falls across the Moon, proving that our planet casting the shadow is round and not flat as long believed. (To their credit, some ancient sky watchers made this connection centuries ago.) Another is the brightness of the Moon during totality which depends on the amount of cloud cover, pollution, and dust and smoke in our atmosphere at that time. This also affects the color seen, which is usually a deep coppery-red in hue. There have been some eclipses (especially following volcanic eruptions) so dark that the Moon was nearly invisible! One additional thing to take note of is where in the sky the eclipse begins—and where it ends. This movement is a result of the Earth itself spinning eastward.
Binoculars are the ideal instrument for watching eclipses, with their low magnifications and wider fields of view being better than the higher powers and limited fields of typical telescopes. Seeing the Moon completely surrounded by lots of sky makes it appear to be floating in space. This impression is additionally enhanced with binoculars since using both eyes gives a sense of depth perception.
As an aside, the Earth actually had two shadows extending out into space—the dark inner umbra discussed above and a very pale large outer one called the penumbra. The Moon slightly dims upon entering it and so for those who might like to try detecting it, our satellite enters it at 9:02 p.m. EDT on the 15th and finally leaves it at 2:51 a.m. on the 16th. Here’s wishing you clear skies wherever you are on eclipse night!
—James Mullaney Former assistant editor at Sky & Telescope magazine & author of 10 books on stargazing. His latest, Celebrating the Universe!, is available from HayHouse.com.
