At precisely 6:34 p.m. Eastern Daylight Time on June 20, the sun will appear to pause in the sky as it changes direction relative to our viewpoint, and it will officially be summer. About 12 hours earlier, at 7:02 a.m., the moon will hit its fullest point for the month.
Together the two heavenly bodies will shower Mother Earth with a full 24 hours of light.
The two phenomenon—summer solstice and the full moon—have not occurred on the same day since 1967, according to Earthsky.org. Though the June full moon, also known as a strawberry moon for its hue, may have last coincided with the summer solstice in 1948, The Old Farmer’s Almanac tells us. It partly depends on which time zone one measures from, according to Atlas Obscura. Either way, it heralds summer, at least in the Northern Hemisphere. It ushers in winter south of the Equator.
“On the day of the June Solstice, the sun reaches its northernmost position, as seen from the Earth,” explains Timeanddate.com. “At that moment, its zenith does not move north or south as during most other days of the year, but it stands still at the Tropic of Cancer. It then reverses its direction and starts moving south again.”
It’s the tilt of the Earth’s axis, rather than its distance from the sun, that creates the seasons, Timeanddate.com notes. And in fact we are farthest from the sun at this time of year.
Indigenous Peoples have observed the solstice with great ceremony since time immemorial, and celebrations continue to this day, some of them resurrecting ancient commemorations. In fact those who show up at dawn to Old Stone Fort State Archaeological Park in Tennessee on Monday June 20 will get to witness the sunrise as American Indians did 2,000 years ago, according to the Tullahoma News. And on Tuesday June 21 a sunrise event will be held at Chaco Canyon in New Mexico.
And somewhere in the middle of that sunrise, the moon will hit its full point. This makes for luscious viewing both the night before and after the solstice.
“Full Moon officially arrives at 7:02 a.m. EDT, but it looks completely illuminated throughout the night,” says Astronomy.com. “It appears low in the southeast as the Sun sets and reaches its peak in the south around 1 a.m. local daylight time.”
Everything the sun does on this day, the moon does its opposite. The sun is at its highest arc in the sky, making it fun to watch one’s stubby shadow around lunchtime. Likewise, the moon will take on a bright, pinkish/amber hue, and dip oh so low.
“The sun gets super high, so this moon must be super-low,” the Old Farmer’s Almanac says. “Even at its loftiest at 1 a.m., it’s downright wimpy-low. This forces its light through thicker air, which also tends to be humid this time of year, and the combination typically makes it amber colored. This is the true Honey Moon.”
It’s also termed the Strawberry Moon, since it can also appear pinkish.
“The moment of full Moon is early Monday morning,” notes The Old Farmer’s Almanac. “So it will look equally full on Sunday night and Monday night. You get two chances to enjoy the solstice honeymoon.”
But for the tilt of Mother Earth’s axis, we might have no seasons to speak of, says The Old Farmer’s Almanac, as with Mercury, whose axis is not tilted at all. Or the seasons could last two decades, as with Uranus, whose 98-degree tilt makes for 21-year-long seasons. On Earth, where everything (for now) is just right, we have sparkling sunny days and can shed our winter gear for a few burden-free months.
“The ease of the season,” says Sky and Telescope, “all boils down to a simple astronomical fact—the tilt of Earth's axis. Whatever protoplanet came along billions of years ago to give ours a proper whack and tip us over on our side 23.5 degrees—thank you.”