Summit County Citizens Voice

About one-third of moon’s face will be blocked by Earth’s shadow

A NASA file image from a past eclipse previews what sky watchers may see June 4.

By Summit Voice

SUMMIT COUNTY — As part of a triple play for backyard sky watchers, this Monday morning (June 4) will deliver a partial lunar eclipse, when the earth’s shadow will block a little more than one-third of the moon’s face. Visit this NASA web page for details.

The string of celestial events started May 20 with a solar eclipse visible in wide swaths of the West, and continues with the June 5 – 6 transit of Venus, when the solar system’s second planet crosses between the earth and the sun.

The last lunar eclipse visible in the western U.S. was just a few months ago — Dec. 9, to be exact, when sky watchers with a clear view of the western horizon were able to see a total eclipse of the lunar orb.

A partially eclipsed moon sets behind Buffalo Mountain, in Summit County, Colorado, Dec. 9, 2011. Click on the image for more pics. Monday’s eclipse will see the bottom third of the Moon covered by the Earth’s shadow.

Monday’s partial lunar eclipse will peak in the western U.S. at about 4 a.m. MDT, so set your alarm to catch a glimpse. A lunar eclipse occurs when the moon passes directly behind the Earth, thus partially or, in the case of a total lunar eclipse, completely blocking sunlight from illuminating the Moon’s surface.

Lunar eclipses happen when the Sun, Moon and Earth are aligned, with the Earth in the middle — that’s why a lunar eclipse only happens on full moon nights.

Viewers in the eastern U.S. won’t have to get up quite as early, as the eclipse will coincide with the setting “strawberry” moon hanging low in the western sky.

The June full moon earned its moniker from Native Americans, who linked the month with the season for harvesting wild strawberries.

Filed under: Colorado, seasons, world news Tagged: | astronomy, June 4 lunar eclipse, partial lunar eclipse, transit of Venus