Skywatchers in North America will miss this lunar eclipse, but a second one this year will be visible in December, especially in western portions of the continent.
Skywatchers across much of the world are getting set for a total lunar eclipse June 15 that promises to shroud the moon in the darkest part of Earth's shadow for 100 minutes – the longest stretch of deep dimming in 11 years.
This eclipse of the moon will not be visible in North America. But people across a broad swath of the planet – from Europe east and south to eastern Australia and New Zealand – will be able to catch at least the darkest phase of the eclipse, weather permitting.
The moon's brightness will take a decided dive during the height of the event, potentially providing skywatchers with good views of features in the night sky they might not otherwise be able to see.
During a 1982 total eclipse that traced a path across the same part of the sky as the June 15 eclipse of the moon, "I was amazed at how brilliantly the summer Milky Way glowed, because it was all but invisible" during the portions of the eclipse when the moon was passing through lighter portions of Earth's shadow, according to Fred Espenak, an astrophysicist at the Goddard Space Flight Center in Greenbelt, Md., in an ecplise forecast he posted on the center's web site.
Total eclipses occur when the moon passes through a dunce-cap shaped shadow Earth casts into space on its night side. The shadow has two main portions – an outer portion, or penumbra, which begins the dimming process, and the umbra, the inner, darkest part of the shadow.