UT Wordmark Primary UT Wordmark Formal Shield Texas UT News Camera Chevron Close Search Copy Link Download File Hamburger Menu Time Stamp Open in browser Load More Pull quote Cloudy and windy Cloudy Partly Cloudy Rain and snow Rain Showers Snow Sunny Thunderstorms Wind and Rain Windy Facebook Instagram LinkedIn Twitter email alert map calendar bullhorn

UT News

Total Lunar Eclipse Coming Before Dawn on Dec. 21

A total lunar eclipse will be visible across North America beginning shortly after midnight Tuesday Central Standard Time, according to the editors of StarDate magazine.

Two color orange horizontal divider

A total lunar eclipse will be visible across North America beginning shortly after midnight Tuesday Central Standard Time, according to the editors of StarDate magazine.

As Earth’s long shadow falls across the moon, the part in the shadow will turn dark. It will look as though a chunk were missing from the moon. About 70 minutes later, the shadow will completely cover the moon, an event known as “totality.” This will last for more than an hour, then the shadow will exit the moon’s opposite side over another hour or so.

The entire event will last just over three and a half hours and can be seen from coast to coast.

High-resolution images and high-definition animation for four U.S. time zones are available online at StarDate’s Media Center. There, you can also sign up to receive advanced e-mail notices of future skywatching events.

Eclipse times for four U.S. time zones are listed at the end of this release. Note that the eclipse begins on Dec. 20 in the Pacific and Mountain time zones, and on Dec. 21 in the Central and Eastern time zones.

On average, there are two or three lunar eclipses a year. They occur when the alignment of the sun, Earth, and full moon is just right, so the moon passes through Earth’s shadow. If the shadow completely engulfs the moon, as in this case, it’s a total eclipse. But if the shadow covers only part of the lunar disk, then it’s a partial eclipse, as occurred in June.

Published bi-monthly by The University of Texas at Austin McDonald Observatory, StarDate magazine provides readers with skywatching tips, skymaps, beautiful astronomical photos, astronomy news and features, and a 32-page Sky Almanac each January.

Established in 1932, The University of Texas at Austin McDonald Observatory near Fort Davis, Texas, hosts multiple telescopes undertaking a wide range of astronomical research under the darkest night skies of any professional observatory in the continental United States. McDonald is home to the consortium-run Hobby-Eberly Telescope, one of the world’s largest, which will soon be upgraded to begin the HET Dark Energy Experiment. An internationally known leader in astronomy education and outreach, McDonald Observatory is also pioneering the next generation of astronomical research as a founding partner of the Giant Magellan Telescope.

Notes: Time-zone specific animations and still graphics are available online. Eclipse times for U.S. time zones are:


Eclipse begins  1:32 a.m.

Mid-eclipse     3:17 a.m.

Eclipse ends    5:01 a.m.

Totality        2:41-3:53 a.m.


Eclipse begins  12:32 a.m.

Mid-eclipse     2:17 a.m.

Eclipse ends    4:01 a.m.

Totality        1:41-2:53 a.m.


Eclipse begins  11:32 p.m.

Mid-eclipse     1:17 a.m.

Eclipse ends    3:01 a.m.

Totality        12:41-1:53 a.m.


Eclipse begins  10:32 p.m.

Mid-eclipse     12:17 a.m.

Eclipse ends    2:01 a.m.

Totality        11:41 p.m.-12:53 a.m.