For all stargazers—and really, who isn’t one at heart?—an extraordinary celestial feast is unfolding right now. Alongside Comet 109P/Swift-Tuttle, which gifts us with the year’s most spectacular meteor shower, a stunning lunar eclipse is about to grace the skies, visible to nearly 60% of the world’s population.
But the Moon isn’t done dazzling us yet. Beyond these headline events, it offers smaller, mesmerizing wonders like the mysterious Lunar X and the haunting Eyes of Clavius crater. This month, it’s time to set your sights on a rare spectacle: the “Seven Sisters Eclipse.”
On July 20, viewers across the US and Canada will witness the fading crescent Moon glide directly in front of the Pleiades star cluster—known as the Seven Sisters—briefly hiding these sparkling gems from view. It’s a magical moment that no lover of the night sky should miss.
Commonly known as the Pleiades or the Seven Sisters, M45 is a dazzling open star cluster made up of over a thousand stars loosely held together by gravity, though it’s the handful of brightest stars that truly steal the show, NASA explains.
This celestial cluster has been admired by humans since ancient times, so it has no recorded discoverer. However, Galileo Galilei—the famed Italian scientist who first observed Jupiter’s largest moons and championed the heliocentric solar system—was the first to gaze upon the Pleiades through a telescope. Located roughly 445 light-years away in the constellation Taurus, M45 shines brightly with an apparent magnitude of 1.6, easily visible to the naked eye, although the exact distance remains a subject of debate.
Despite the name “Seven Sisters,” only six stars shine brightly enough to be seen without aid. One sister is mysteriously absent from many global stories. Earlier research suggests that a seventh star may have been visible long ago but now hides too close to another star in the sky to be easily distinguished. Some astronomers even speculate that the myth of the Seven Sisters could be the oldest story ever told, thanks to the ancient visibility of this elusive seventh star.
Interestingly, this particular eclipse—where the Moon passes in front of the Pleiades—is not as rare as it might seem. According to timeanddate.com, this event has been occurring monthly since September 2023 and will continue to do so until July 2029.
“The Moon shifts its position against the backdrop of stars as it orbits Earth every 27.3 days, so it will next cross paths with the Pleiades on August 16,” explained Anna Gammon-Ross, an astronomer at the Royal Greenwich Observatory, in an interview with Discover Magazine.
However, as the Moon journeys through its orbit, its height in the sky changes—sometimes it passes above the Pleiades, other times below, and on rare occasions like July 20, it will glide directly in front of this dazzling star cluster.
This “Seven Sisters Eclipse” will be visible to the naked eye. In the early hours of Sunday morning, simply look toward the horizon to spot the shimmering Seven Sisters. Then, watch closely as the Moon slowly drifts across the sky, briefly hiding these sparkling stars from view—a breathtaking celestial dance you won’t want to miss.