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Prelude to the 2017 Total Solar Eclipse: A Partial Lunar Eclipse Occurs Monday

By Bhanumathe                                                    August 7, 2017                Much of the Eastern Hemisphere will be treated to a partial eclipse of the moon Monday (Aug. 7) — a prelude to the grand spectacle that awaits North Americans exactly two weeks later.

The lunar eclipse will be visible from parts of Europe, Africa, Asia and Australia, and peaks 2:20 p.m. EDT (1820 GMT). Even if you're not in the path of the partial lunar eclipse, Monday will bring a summer full moon to the night sky. Traditionally, some Native American fishing tribes were aware that sturgeon — a large fish that inhabited the Great Lakes as well as Lake Champlain — were most readily caught around the time of the August full moon, hence it became known as the Full Sturgeon Moon. A few tribes knew it as the Full Red Moon because, as the moon rises, it appears reddish through any sultry haze. It was also called the Green Corn Moon or the Grain Moon.     

Unfortunately, the Americas are completely shutout of seeing this upcoming lunar event, since that part of the Earth will be turned away from the moon and will be in daylight when the eclipse takes place. Depending on where you are in the United States, this eclipse takes place during the late morning to early afternoon, when the moon is below the horizon.

Conversely, most of Asia, Indonesia and Australia will be facing the moon when it skims through the northern tip of the Earth's dark umbra. For these locations, the eclipse will take place chiefly during the after-midnight hours of Tuesday (Aug. 8).

For Western Europe, the moon will either rise on Monday evening with the last vestige of the umbra still visible on the moon's western limb (eastern Spain, most of France, central and southern Sweden), or it will have just moved off the moon's disk completely (western Spain, Portugal, the United Kingdom and Norway). All of these locations will see the last smudge of the penumbral shadow leave the moon around 19:45 UTC. 

At maximum eclipse (18:20 UTC), umbral penetration will fall just shy of magnitude 0.25, meaning the moon's southern quarter will be submerged in the Earth's dark umbral shadow. For those who are able to view this eclipse, probably the most interesting thing to watch with binoculars or a telescope is when the umbra moves over the dazzling lunar crater Tycho, briefly plunging it into darkness between 18:07 and 18:40 UTC. 

With or without a telescope, the most striking effect will come between 17:22 and 19:18 UTC: The smooth curve of the dark umbra on the lunar disk will be a nice reminder to us, as it was a divine revelation to the ancient Greeks, that our Earth is round.

Here is a timetable for the eclipse; times are given in Coordinated Universal Time/GMT, which is four hours ahead of Eastern Daylight Time. 

Partial Lunar Eclipse of August 7, 2017