First Major Lunar Standstill to Occur After 18 Years

Skywatchers have more to look forward to this year than solely the April 8th total solar eclipse and stunning auroras. For the first time since 2006, there will be a “major lunar standstill.” During this event, the moon will rise and set at its furthest points to the north and south on the horizon. This marks the highest and lowest points in its 18.6-year cycle.

The moon’s path across the sky differs from the sun’s because of the way the Earth and moon navigate. Our solar system is essentially flat with planets orbiting the sun on a level called the ecliptic.

Earth spins tilted at 23.4 degrees compared to this plane, which makes the sun appear to rise and set over nearly 47 degrees—a span it travels across in a year. The moon’s orbit tilts 5.1 degrees relative to the ecliptic, so it rises and sets within about a 57-degree range each month, as reported by Live Science.

This is why the moon might appear to rise and set at points on the horizon that are further north or south than where the sun rises and sets.

Earth and the moon tilt to their maximum extent

A major lunar standstill, also known as a lunistice, occurs when both Earth and the Moon are tilted to their maximum extents. During this phase, the Moon rises and sets at its farthest points on the horizon. It rises at its highest northeasterly point and sets at its highest northwesterly point. Similarly, it rises at its most southeasterly point and sets at its most southwesterly point.

Look at the moon tonite. It will be at its highest point in the last 19yrs, especially around 7.56pm when it will be due south. This will happen every 27.5 days for the whole of 2024-25 — part of a phenomenon known as the major lunar standstill. Watch this space for updates… pic.twitter.com/VIKyQkIUlj

— Fabio Silva (@FSilva_skyscape) February 18, 2024

This event significantly affects how long the Moon remains visible in the night sky. When the Moon rises farthest northeast in the Northern Hemisphere during a major lunar standstill, it moves higher into the sky and stays visible for a longer duration. Its position in the sky is noticeably different compared to a minor lunar standstill, when its rising and setting points are closest together.

Historical sites such as Stonehenge, Callanish, and Newgrange are believed to have alignments with specific moonrise and moonset points during major lunar standstills, as reported by Live Science.

Likely to occur between September 2024 and March 2025

The major lunar standstill will reach its peak around the equinoxes in September 2024 and March 2025. However, seeing it clearly depends on factors like the Moon’s phase, one’s location, and weather conditions. Good times to observe this phenomenon include when the moon rises as the sun sets and when the Moon sets as the Sun rises, especially during a full moon.

For example, on June 21st, the Sun will rise and set at its farthest northeasterly and northwesterly points, while the full Strawberry Moon will rise and set at its most northeasterly and northwesterly positions.

Conversely, on December 15th, the sun will rise and set at its farthest southeasterly and southwesterly points, while the full Cold Moon will rise and set at its most northeasterly and northwesterly points, as reported by Live Science.