A partially eclipsed full moon hangs in the evening sky over Belgrade, Serbia, on Wednesday during the start of a total lunar eclipse. The sight heralded the longest and deepest total lunar eclipse seen in more than a decade.

"The path that the moon is taking through Earth's shadow is almost directly through [the shadow's] center, making for the longest possible path and so the longest duration," said Ben Burress, staff astronomer at the Chabot Space & Science Center in Oakland, California.

Earth's shadow started to darken the moon around 18:22 universal time, or UT (2:22 p.m. eastern time). The period when the moon is completely engulfed in Earth's shadow—known as totality—began at 19:22 UT and lasted for almost two hours.

"The last eclipse that was as long as this one was in 2000, while the next won't be until 2018, so this makes it a somewhat rare event."

(Submit your June 15 lunar eclipse pictures and we may run them on National Geographic News. Be sure to use the word "eclipse.")

—With reporting by Andrew Fazekas

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