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On August 28, the Moon will plunge through Earth's shadow, and the United States' West Coast sees the best show.

The March 3, 2007, lunar eclipse favored Africa, Europe, and Asia. Anthony Ayiomamitis

The spectacular eclipse occurs the morning of August 28. Circumstances favor observers west of the Mississippi, who missed out on the March lunar eclipse. Better still, this event marks the first central lunar eclipse since 2000.

A central eclipse is one where part of the Moon passes through the center of Earth's shadow. This results in a longer-lasting eclipse, and it likely will result in a more darkly colored Moon at totality. The Moon's northern edge passes through the shadow's center, which means its northern half will look noticeably darker than its southern half.

The penumbral part of the eclipse begins at 3:54 a.m. Eastern Daylight Time. The first hint of shadow won't be visible to East Coast observers until at least 4:30 a.m. Watch the Moon low in the southwest as the limb near Oceanus Procellarum gradually darkens.

The umbral eclipse phase begins at 4:51 a.m. EDT. It takes an hour for the Moon to fully enter Earth's shadow. But by the time it does, twilight brightens the sky. For observers on the East Coast, the Moon sets while totally eclipsed.

The farther west you go, the higher the Moon's altitude during totality. West of the Rockies, observers see all but the eclipse's final penumbral stages. Totality begins at 4:52 a.m. Central Daylight Time, and mideclipse occurs at 5:37 a.m. CDT.

Try estimating the Moon's darkness at mideclipse. French astronomer André Louis Danjon (1890–1967) devised a simple scale for comparing the depth of lunar eclipses. It runs from 0 (the Moon is almost invisible) to 4 (the Moon is a bright, coppery red). See sunearth.gsfc.nasa.gov/eclipse for more details.

The Midwest will see totality in a gradually brightening sky, with the Moon 6° high by totality's end. From cities like Denver, perched along the Great Divide's eastern edge, observers may find mountains block the view during the eclipse's later stages.

The West Coast will see the eclipse in its entirety and high in the sky, well placed for observing. In Hawaii, the eclipse occurs near local midnight August 27/28.