Not all Full Moons are created the same. Follow the familiar Moon long enough, and you’ll notice something strange, as it seems to wander across the sky from north to south, from one cycle to the next.
Welcome to the fantastic precession of our natural satellite, the Moon.
Last December, we saw the ‘Long Night’s Full Moon,’ as the Full Moon nearest to the solstice rode the highest in the sky for the last two decades. Now, its time for the Southern Hemisphere to get a turn, as the Moon heads steeply southward, on its way to full on June 11th.
The cycle is a product of the unique orbit of our Moon. Fun fact: the unique orbit of the Moon is tilted 5.15 degrees not in respect to our rotational axis… but versus the ecliptic, the plane of the path of the Earth around the Sun.
This means that the Moon can range anywhere from 28.65 degrees declination south to north in the sky. That’s 23.5 degrees (the tilt of the Earth’s axis) plus 5.15 degrees (the inclination of the orbit of the Moon versus the ecliptic).
The five degree tilt of the Moon’s orbit is also why we don’t see eclipses every lunation, and instead see them bookending biannual eclipse seasons.
Now, this doesn’t happen on most years. The cycle spans almost a 20 year generation, at 18.6 years from one Major Lunar Standstill to the next. In between those ‘hilly’ years, the Moon’s path versus the ecliptic goes ‘shallow’ versus the ecliptic, known as a Minor Lunar Standstill.
2006 was the last Major Lunar Standstill, with 2025 seeing the node crossing occurring on January 29th. After this year, the apparent path of the Moon begins to shallow out once again. This works because the Moon’s orbit is actually being slowly dragged around once every 18.6 years (mostly due to the pull of the Sun) in what’s known as the nodal precession.
Here’s another fun fact: the Moon can actually appear in 18 modern constellations: the 12 zodiacal constellations, plus Ophiuchus, Sextans, Orion, Auriga, Crater, and Corvus.
The importance of the long night’s Moon wasn’t lost on ancient peoples, as a way to mark longer periods of time. The Callanish Stones in modern day Scotland erected in the Bronze Age have been found to align with the rising and setting of the wide ranging Moon.
The Full Moon in June 2025 occurs on the 10th/11th, just 10 days prior to the June southward solstice. The June Full Moon is also sometimes called the Strawberry Moon.
From mid-northern latitudes, the June 2025 Full Moon will really skim the treetops to the south… while ‘north of the 60’ in places such as Alaska, Greenland and Iceland, the Moon will fail to rise at all. Meanwhile, southerners will experience their very own ‘Long Night’s Moon’ riding high in the June sky.
The Moon also occults Spica on June 6th for Tasmania and southern New Zealand, and Antares for Australia and New Zealand on the 10th, just before reaching Full. Regulus will join the Moon’s occultation route in July. This starts a rare time when three of the four bright fourth magnitude stars the Moon can currently occult lie along the Moon’s path. Only Aldebaran is the odd star out.
If skies are clear, be sure to note the position of the rising Full Moon on the evenings of the 10th and 11th. Wherever you happen to observe from is your own personal ‘observatory,’ be it your yard, driveway or hilltop… and it’s always fascinating to note the local limits of your site.
While deep-sky imagers may curse the Moon, we can be thankful that our Moon has provided our species with a fine lesson in celestial mechanics, as it lights our path to the stars.
This article was originally published by Universe Today. Read the original article.
