In what's called a conjunction, the waxing crescent moon will pass very close to the planet Venus, with the closest approach occurring around 3 p.m. ET.

At that point the cosmic pair will be low and close together in the sky in the southeast, explained Ben Burress, staff astronomer at the Chabot Space and Science Center in Oakland, California.

"Daylight, however, will make seeing either of them difficult at best, so the best time to see them will be after sunset."

While this is an unusually close conjunction between the moon and a planet for most of the world, some lucky observers in parts of South America will witness Venus actually disappear behind the moon. (See a picture of a 2012