A RARE astronomical event that only happens once every 18 years is happening again.
There is talk of a great lunar standstill – and some even think it is linked to Stonehenge.
WHAT IS A MOON PHASE STILL?
A major lunar standstill is an event that occurs every 18.6 years.
Set over several months, it sees the moon take a more dramatic path across the globe sky.
The reasons why are very complicated, but ultimately it is related to the angle between the moon and the celestial equator (its declination).
Normally the moon rises and sets in approximately the same place.
But during a major lunar standstill, the tilt makes a bigger swing and the moon rises further north and south.
In practice, this means that the moon appears to move differently than normal.
The points on the horizon where the moon rises and sets are at their northernmost and southernmost points during a major lunar standstill.
It means we see steeper angles, with the moon appearing to rise much higher on some nights – and also appearing to peak lower on other nights.
In fact, the highest and lowest points of the moon’s position in the sky are more extreme than would normally be the case.
When can you see the lunar standstill?
The great lunar standstill is not something that happens in one day, but over a period of time.
The last time we saw a major standstill was in 2006.
The next one one begins in 2024, when the moon’s declination becomes more extreme.
The moon – our nearest neighbor explained
This is what you need to know…
- The moon is a natural satellite – a spacefaring body that orbits a planet
- It is Earth’s only natural satellite and the fifth largest in the solar system
- The moon has a diameter of 3,450 kilometers, about 0.27 times the diameter of the Earth
- Temperatures on the moon range from minus 173 degrees Celsius to 260 degrees Celsius
- Experts assumed the moon was another planet until Nicolaus Copernicus explained his theory of our solar system in 1543.
- It was eventually assigned to a ‘class’ after Galileo discovered four moons orbiting Jupiter in 1610
- The moon is believed to have formed about 4.51 billion years ago
- The strength of its gravitational field is about one-sixth of Earth’s gravity
- The Earth and the moon have ‘synchronous rotation’, meaning we always see the same side of the moon – hence the expression ‘dark side of the moon’
- The moon’s surface is actually dark, but appears bright in the sky because of the reflective ground
- During a solar eclipse, the moon almost completely covers the sun. Both objects appear the same size in the sky, because the Sun is both 400 times larger and further away
- The first spacecraft to reach the moon was in 1959, as part of the Soviet Union’s lunar program
- The first crewed orbital mission was NASA’s Apollo 8 in 1968
- And the first manned moon landing took place in 1969, as part of the Apollo 11 mission
For avid skywatchers, the standstill is expected to be most extreme in late 2024 to early 2025.
The best chances to see the effects are during full moons.
Here is a list of upcoming Full Moons:
- June 21, 2024
- July 21, 2024
- August 19, 2024
- September 17, 2024
- October 17, 2024
- November 15, 2024
- December 15, 2024
- January 13, 2025
- February 12, 2025
- March 14, 2025
- April 12, 2025
- May 12, 2025
- June 11, 2025
- July 10, 2025
- August 9, 2025
- September 7, 2025
- October 6, 2025
- November 4, 2025
- December 4, 2025
It is believed that at least one major standstill was marked during Stonehenge’s early phase, which may have influenced the design and purpose of the monument.
English heritage
The best time to see the effects of the standstill is around the equinoxes in September 2024 and March 2025.
The equinoxes are when the lengths of days and nights are approximately equal.
If you regularly look at the moon from the same location, you should see significant changes in the way it appears to move across the sky over the weeks and months.
The upcoming equinoxes are expected to occur on September 22, 2024 and March 20, 2025.
HOW DOES IT CONNECT WITH STONEHENGE?
Some experts believe that the mysterious Stonehenge monument in England is linked to major lunar standstills.
“It is believed that there was at least one major standstill during the early phase of Stonehenge, which may have influenced the design and purpose of the monument,” explains English Heritage.
The organization continues: “During a major lunar standstill, the moon rises and sets at a spot on the horizon that the sun never reaches.
“For people who follow the sun’s movement throughout the year – such as farming communities who use horizon calendars for planting and harvesting – the appearance of the moon further north and south than the sun’s extremes may have been of great importance .
“Perhaps this would have been a moment when the moon god was stronger than the sun god.
“The great lunar standstill, which occurred only once every nineteen years, is said to have been a generational event – spoken of in the stories passed orally from one generation to the next.”
English Heritage will also livestream the southernmost moonrise from Stonehenge on its YouTube channel on June 21.