First Quarter tonight. Roughly half the face is lit up. NASA’s daily guide pegs it at exactly 48%, give or take a rounding error.
Looking Up
Naked eye view first. You can spot the dark patches—the seas. Mares Crisium. Tranquillitatis. Fecunditatis. They look like shadows on the surface but are actually flat basalt plains.
Want more? Grab binoculars. Endymion crater appears. So does Posidonius. Push the budget and get a telescope. You’ll actually see where Apollo 11, 14, and 15 touched down. Wait—14 is in the shadowed side mostly? Check the phase angle. But yeah, the landing sites are there, frozen in regolith.
“The Moon doesn’t change. The angle does.”
Full Moon Soon?
Yes. Another one. May 31. That’s a week from now. Two full moons in one month happens, don’t worry, but only because May starts with a New Moon and the lunar calendar doesn’t care about human grids.
Why Does It Shift?
29.5 days. That’s the orbit time. Earth-centric. We lock onto the same side because of tidal forces, but the sun? The sun keeps moving. As the moon loops around, sunlight hits it from different angles. Hence the phases. New, waxing, full, waning. Simple geometry, mostly.
- New Moon: Hidden. Dark side faces us. Between Earth and Sun.
- Waxing Crescent: Sliver of light. Right side in the north.
- First Quarter: Half-lit. Right side again. Looks like a semicolon.
- Waxing Gibbous: Almost there. More than half lit.
- Full Moon: Entire face lit.
- Waning Gibbous: Starting to fade.
- Third Quarter: Left half lit.
- Waning Crescent: Fading out. Back to black.
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What does it mean if the sky is clear tomorrow? 🌙
