July 2018 lunar eclipse

A total lunar eclipse occurred at the Moon’s descending node of orbit on Friday, July 27, 2018, with an umbral magnitude of 1.6100. It was a central lunar eclipse, in which part of the Moon passed through the center of the Earth's shadow. A lunar eclipse occurs when the Moon moves into the Earth's shadow, causing the Moon to be darkened. A total lunar eclipse occurs when the Moon's near side entirely passes into the Earth's umbral shadow. Unlike a solar eclipse, which can only be viewed from a relatively small area of the world, a lunar eclipse may be viewed from anywhere on the night side of Earth. A total lunar eclipse can last up to nearly two hours, while a total solar eclipse lasts only a few minutes at any given place, because the Moon's shadow is smaller. Occurring about 19 hours after apogee (on July 27, 2018, at 1:45 UTC), the Moon's apparent diameter was smaller.

This was the first central lunar eclipse since June 15, 2011. It was also the longest total lunar eclipse of the 21st century, but not the longest in the 3rd millennium. Totality lasted one hour and 42.955 minutes, a period "just short of the theoretical limit of a lunar eclipse (one hour and 46.605 minutes)". The Moon remained at least partially in Earth's shadow for three hours 54.55 minutes. The longest total lunar eclipse of the 3rd millennium will occur on May 12, 2264, lasting 106 minutes and 13.2 seconds, which will be the longest total lunar eclipse since 2000, and the longest one until 3107.

The eclipse occurred when the Moon was near its maximum distance from Earth, which caused the Moon to appear smaller than normal (a phenomenon sometimes called a micromoon), and to travel at its slowest speed in its orbit around Earth.

This lunar eclipse coincided with Mars being nearly as close as possible to Earth, a concurrence that happens once every 25,000 years.