This month, five planets visible to the naked eye are aligning in the sky in a "special" parade that hasn't been seen for 18 years.
While seeing two or three planets close together in the sky—what's known as a conjunction—is a relatively common occurrence, having five together is "unusual," Robert Massey, the deputy executive director of the U.K. Royal Astronomical Society, told Newsweek.
But that's not all. There is something extra special about this particular planetary alignment, according to Diana Hannikainen, observing editor of Sky & Telescope magazine.
"And that is that the five naked-eye planets are strung across the sky in the same sequential order as they orbit the sun: Mercury, Venus, Mars, Jupiter, Saturn," she told Newsweek. "They just happen to be positioned in their physical orbits around the sun so that we see them so in the dawn sky."
The last time a similar lineup took place with the five planets in sequence was back in 2004 when they were visible in the evening sky, Massey said.