Overview
- The second full moon in May — called a Blue Moon because it is the month’s second full moon — reached its official peak at 10:45 on Sunday, May 31.
- That peak happened while the Moon was below the horizon for many places, so observers will see the full moon after sunset during moonrise rather than at the exact peak time.
- The May 31 Moon is a micromoon because it reaches near‑apogee the next day, about 406,366 kilometers from Earth, which makes its apparent disk a few percent smaller than average.
- Watch for the moonrise for the most striking view because the human brain makes the low Moon look larger against foreground objects, an effect that does not appear in photos.
- Astrology pieces note the full moon sits in Sagittarius and name Sagittarius, Gemini, Virgo and Pisces as signs likely to feel the event, and experts say Blue Moons occur roughly every 2.5 years.