This is it—tonight's the night. The only total lunar eclipse of 2025 that will be visible from much of the Americas is about to unfold. If you're anything like me, you'll be crossing your fingers for clear skies and setting your alarm for some late-night viewing of this fantastic celestial spectacle.
A total lunar eclipse occurs when Earth's shadow falls across the full moon; at the event's apex, sunlight shining through our planet's upper atmosphere tints our normally monochrome natural satellite into a breathtakingly beautiful (but somewhat spooky) blood-red orb. But from beginning to end the entire process stretches across several hours, and not all of its stages are quite so dramatic.
As our resident astronomer and columnist Phil Plait explains: "Astronomers divide the eclipse into several stages. First contact is when the moon's leading edge moves into the penumbra [the outer part of Earth's shadow]. Second contact is when the leading edge enters the umbra [the deepest part of Earth's shadow]; this is also the start of the partial eclipse, when Earth's shadow falling on the moon becomes obvious. Third contact is when totality occurs. Fourth contact is when the leading edge passes out of the umbra and becomes easily visible again, ending totality, and fifth contact is when the entire moon is fully out of the umbra. Sixth contact is when the moon leaves the penumbra and the eclipse is officially over."
I mention all this because, of course, what self-respecting newsletter editor would tease readers with a tantalizing celestial event without offering a handy step-by-step timeline of its unfolding? Certainly not I. Here's a handy list of tonight's total lunar eclipse stages to help guide your viewing, with all times in EDT:
First contact: 11:57 P.M. (eclipse begins)
Second contact: 1:09 A.M. (partial begins)
Third contact: 2:26 A.M. (totality begins)
Fourth contact: 3:32 A.M. (totality ends)
Fifth contact: 4:48 A.M. (partial ends)
Sixth contact: 6:00 A.M. (eclipse ends)
There may even be some science in the offing, too. After a flawless touchdown earlier this month, Firefly Aerospace's Blue Ghost lunar lander is still alive and kicking on the moon's near side, and its landing site will be engulfed in Earth's shadow. Blue Ghost will likely capture some gorgeous images—and maybe even some useful data—of the eclipse as seen from the lunar surface. —Lee Billings
