Tonight, the shadow of the Earth will drape fully across the moon, turning its typical gray glow into an ominous rust red. Starting around 2 a.m. Eastern time, on Tuesday morning, the moon will begin to slip into the Earth's shadow, and from 3:06 to 4:24 am, it will be fully immersed, with the Earth blocking any sunlight from reaching its satellite.
As a simple matter of geometry, lunar eclipses tend to be more common than their solar counterparts. Though you're likely to get a shot to see a lunar eclipse every few years, Cornell's astronomy department says that “at any single location on Earth, a total solar eclipse occurs only once every 300 years or so.”
Lunar eclipses are also much less finicky: for a solar eclipse you need to be on the right spot on Earth to really get the full show. Lunar eclipses, meanwhile, says ABC, “can be viewed almost anywhere on the night side of the Earth (provided it's clear).” If you want to be up for tonight's show but your view gets obscured by clouds, NASA will be covering the event starting at 2 am Eastern time. The SLOOH observatory will also be putting on a show.
According to an online eclipse calculator, the nation's capital should be in for another total lunar eclipse in October, and another next fall. Such a high frequency of recurring eclipses, says National Geographic, is a rare occurrence.