A partial lunar eclipse is happening tonight! A lunar eclipse occurs when Earth gets in the way of the Sun’s light hitting the Moon. That means that during the night, the Moon fades away as Earth’s shadow covers it up. There are three types: total, partial and penumbral. You're probably most familiar with a total lunar eclipse. That's when Earth's umbra, the darkest part of its shadow, covers up all of the Moon's surface. Penumbral lunar eclipses happen when the Moon travels through the faint penumbral portion of Earth’s shadow. Finally, when only part of the Moon's surface is obscured by Earth’s umbra, it's known as a partial lunar eclipse.
Map showing the visibility of the Nov. 18-19 partial lunar eclipse. Darker areas indicate greater visibility. Check local details for visibility near you. Credit: NASA/JPL-Caltech
In our area the eclipse will last 3 hours and 28 minutes with 97% of the moon in shadow during the fullest part of the eclipse. This is the longest partial lunar eclipse that has happened in the last 580 years and it will hold onto that record until 2669, according to NASA. You may also notice the moon takes on a red color during the eclipse. That happens for the same reason the sunset can turn red - sunlight is passing through more of our atmosphere. During the eclipse, the sunlight will pass through Earth's atmosphere before reaching the moon so it will take on that reddish color. Click here to read more about why we see red in these situations.
Here's the timeline of what to expect overnight:
Penumbral Eclipse Begins: 1:02 a.m. EST
Partial Eclipse Begins: 2:19 a.m. EST
Greatest Eclipse: 4:03 a.m. EST
Partial Eclipse Ends: 5:47 a.m. EST
Penumbral Eclipse Ends: 7:04 a.m. EST