A partial lunar eclipse will be visible across much of North America early Saturday morning, 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.
High-resolution images and high-definition video are available online at StarDate's Media Center. There, you can also sign up to receive advanced e-mail notices of future skywatching events.
The best part of the eclipse begins when the moon first touches the dark inner part of the shadow around 5:17 a.m. Central Daylight Time. The eclipse reaches its peak about 80 minutes later and ends when the moon exits the shadow at 8 a.m. For eclipse viewing times for other U.S. time zones, and what viewers in different parts of the country can expect to see, refer to the notes at the end of this release.
Except for most of the East Coast, the early stages of the eclipse will be visible across most of the U.S. As the eclipse goes on, though, the moon will set across the central and western regions of the country. Most of the country will get to see at least some of the eclipse. The entire eclipse will be visible across the Pacific Basin, including Hawaii.
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 the shadow. If the shadow completely engulfs the moon, it's a total eclipse. There'll be one of those in December, with those in the United States in perfect position to see it. But if the shadow covers only part of the lunar disk, it's a partial eclipse. That's what happens Saturday.
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.
Note: Time-zone specific animations and still graphics are available at http://stardate.org/mediacenter.
Eastern Time Zone Views: The eclipse will be invisible to almost everyone in the Eastern time zone because the moon either will be below the horizon as the eclipse begins, or nearly so, as in the westernmost parts of the time zone like Louisville, Ky., and Atlanta.
Central Time Zone Views: The eclipse begins at 5:17 a.m., reaches greatest eclipse at 6:38 a.m., and ends at 8 a.m. The majority of viewers in the Central time zone will see most of the eclipse. Those in the easternmost areas of the time zone, like Chicago and Memphis, won't see much because the moon will have set or be sinking below the horizon as the eclipse begins. But folks in the central and westernmost parts of the Central time zone, including most of Texas, will see the majority of the event, from the beginning through greatest eclipse and some of the waning of the eclipse. The moon will sink below the horizon before the eclipse ends.
Mountain Time Zone Views: The eclipse begins at 4:17 a.m., reaches greatest eclipse at 5:38 a.m., and ends at 7 a.m. Everyone in the Mountain time zone will see the beginning of the eclipse. Those in the easternmost portions of the time zone, like Rapid City, S.D., and Denver, will see only the beginning of the event. The moon will sink below the horizon before it reaches greatest eclipse. Those farther west, such as Salt Lake City and Boise, Idaho, will see most of the event, from the beginning, through greatest eclipse, and part of the eclipse's waning. The moon will sink below the horizon before the eclipse ends.
Pacific Time Zone Views: The eclipse begins at 3:17 a.m., reaches greatest eclipse at 4:38 a.m., and ends at 6 a.m. Everyone in the Pacific time zone will see the entire eclipse. The moon will set in the westernmost part of the time zone a few minutes after the eclipse ends.