This Saturday, at exactly 2:06 a.m. EDT, the moon enters its new phase. That part isn’t unusual. What makes this one different is its timing, which earns it the rare title of a black moon.

You won’t be able to spot it in the sky, though. During a new moon, the moon passes between Earth and the sun, which hides its illuminated side from view. It’s still up there, just completely dark to anyone standing on the ground.

This particular new moon is what astronomers call a seasonal black moon, which occurs when four new moons squeeze into a single season instead of the usual three. This one lands in the middle of a packed summer that started with the solstice in late June and ends just before the equinox in September. The black moon falls third in that sequence, which makes it special.

Seasonal black moons show up about once every 33 months, which makes them slightly rarer than the monthly variety. That kind occurs when two new moons fall within the same calendar month. Both types are relatively obscure, though black moons tend to attract attention from people who like their astronomy with a side of symbolism.

You won’t see the moon, but that’s the whole point. With nothing washing out the sky, it’s one of the best nights left this summer to catch the Milky Way from the Northern Hemisphere.

If you want a good view, get away from streetlights and skylines. Look southeast for the Summer Triangle—Vega at the top, Deneb to the left, and Altair below. The Milky Way passes through the triangle, fading as it moves toward the southern skyline.

The moon phases continue whether anyone’s paying attention, but this one offers a celestial reminder to look up. The black moon might not be something you can photograph, but its absence clears the stage for everything else.

Some sky events steal the show. Others step aside so the rest of the universe can do its thing.