In summer, these glorious animal appendages grow like nobody’s business. So much so, they even have their own monuments. Whether adorning a Roman moon goddess in the Louvre or simply a 14,000-pound pile of them in a town square in Wyoming, it’s undeniable: we love buck antlers. We have even named a moon after them.
The full Buck Moon is so-called because its month, July, is notably when male deer (bucks) begin to spectacularly increase the size of their antlers—which are not horns but the fastest-growing bones known to humans—at a blistering rate of 1/4 to 1 inch per day, gaining as much as a pound of weight every 24 hours. They are covered with an exquisite velvet that gets rubbed off and are used to attract mates and fight off challengers.
This month, the full Buck Moon will occur on July 21, at exactly 6:17 a.m. EDT. That means it will have reached its peak illumination, the instant at which a full moon officially becomes full, and is, practically speaking, exactly opposite the sun viewed from Earth. Thus, a moon reaches its fullest and roundest to the extent that fullness and roundness can be achieved in moons. This also means that many places around the world and in North America will not see the moon the second it technically becomes “full.” The very next second it is no longer technically full.
Be that as it may, the moon moves very slowly in its orbit around the Earth, circling once a month, and won’t have changed position much a day or two before or after July 21. You won’t have any problem recognizing a moon that looks full to the human eye around then. Particularly for observers in the aforesaid EDT zone, at 6:17 a.m., the aforesaid time of its technical peak fullness, the full Buck Moon will be below the horizon. So scan the arch of the sky on the nights before or after.
Befitting a full moon of its name, this month’s Buck Moon will be found in the constellation of the archer, Sagittarius (also called the teapot). Less frequently, it falls more easterly in Capricornus the Sea Goat. Both constellations lie about the southern horizon, for observers in the northern hemisphere.
Gazing toward the grove of stars appearing in the pallid sky around sunset, turn toward the east to find the full moon rising; as mentioned, full moons and the sun are directly opposite, so naturally, when one sets in one cardinal direction the other will rise to its opposite. Full Buck Moons tend to hang nearer the horizon as opposed to higher in the sky; as summer suns arc high during the day and stay up longer than winter suns, summer moons do the opposite, hovering lower for shorter durations at night while reversing this trend in winter.
Moon, moons, and more moons. But there will also be planets and notable stars to keep the moon company on July 21. Mercury, Saturn, Mars, and Jupiter will follow the full Buck Moon’s rise and all parade across the sky together. The Summer Triangle of stars will arrive—Vega, Deneb, and Altair—and an upside-down Big Dipper. So weather permitting, grab a loved one as company of your own and savor a cosmic spectacle in the summer air with the moonlight down low.
