November 19, 2021 Almost Total Lunar Eclipse

On November 19 (late evening of the 18^th in some time zones), the Moon passes into the shadow of the Earth, creating a partial lunar eclipse so deep that it can reasonably be called almost total. At the moment of greatest eclipse, at around 9:03 a.m. Universal Time, 99.1% of the Moon's disk will be within the Earth's umbra. This part of the eclipse is visible in all of North America, as well as large parts of South America, Polynesia, eastern Australia, and northeastern Asia.

The penumbra is the part of the Earth's shadow where the Sun is only partially covered by the Earth. The umbra is where the Sun is completely hidden. The Moon's appearance isn't affected much by the penumbra. The real action begins when the Moon starts to disappear as it enters the umbra at about 7:20 a.m. UTC (2:20 Eastern Standard Time, 11:20 p.m. Pacific on the 18^th). An hour or so after that, the part of the Moon still in sunlight will be small enough for observers' eyes to adapt to darkness and perceive the coppery color of the part of the Moon within the umbra. The animations here mimic this dark adaptation by increasing the apparent photographic exposure around the time of greatest eclipse.