In 2005 and 2006 we are in a major lunar standstill season. For several years now some of my astrological camping colleagues and I have been trying to establish what lunar standstills are and when they occur. There is usually no reference to them in most standard astronomy books. Some reference is made to them by authors who have written about ancient megalithic sites such as Callanish on the Isle of Lewis off the west coast of Scotland.
This has been written for astrologers, those interested in megalithic sites and Sun, Earth, Moon astronomy. For readers who are interested, but do not have a great deal of knowledge in astrology, astronomy or archeoastronomy, I have gone back to basics in explaining the cycles of the Sun and Moon, otherwise it is not that easy to understand what lunar standstills are.
The Ecliptic is the annual path of the Sun through the sky as seen from the Earth. Of course it is the Earth that takes a year to orbit the Sun but, from our perspective on Earth, it appears that the Sun is travelling on average just over 1° a day, taking 365¼ days to complete one cycle.
The Earth is tilted on its axis at an angle of 23½°. The Celestial Equator is the Earth's equator projected onto space (the celestial sphere). This means that the ecliptic is inclined to the celestial equator at the same angle. This is why we have seasons.
The ecliptic path is the centre of the Zodiac. The Zodiac extends 8° north and south of the ecliptic and the Tropical Zodiac starts from 0° Aries, usually referred to as the First Point of Aries by astronomers. Astrologers, following the western tradition, use this Zodiac. The Zodiac belt is simply divided into sections of 30° each and these are named Aries, Taurus, Gemini, etc. The Moon follows this Zodiac belt as seen from the Earth.
At the equinoxes days and nights are broadly of equal length. At the March equinox, on about 21st March each year, the Sun is overhead the celestial equator. The Sun is at 0° Aries and it is mid spring in the northern hemisphere and mid autumn in the southern hemisphere. At the September Equinox, on about 22nd September each year, the Sun is again overhead the celestial equator at 0° Libra. It is mid autumn in the northern hemisphere and mid spring in the southern hemisphere.
On about 22 December, the Sun enters 0° Capricorn and is overhead the Tropic of Capricorn at terrestrial latitude 23½° south. During this time it is midwinter in the northern hemisphere and mid summer in the southern hemisphere. On about 21 June, the Sun enters 0° Cancer and is overhead the Tropic of Cancer at terrestrial latitude 23½° north and it is mid summer in the northern hemisphere and mid winter in the southern hemisphere. At the summer solstice the days are at their longest and at the winter solstice the days are at their shortest.
Solstice means Sun's standstill as for about a week during the Solstices in June and December the Sun appears to stand still in its rising and setting positions. Equinox means balance or equal and when the Sun is overhead the celestial equator twice a year in March and September, days and nights are of equal length. The Sun appears to travel fast against its rising and setting positions during the equinoxes.
The Moon takes about 27½ days to orbit the Earth and to travel round the Zodiac from Aries to Pisces. The Moon takes a little longer, about 29½ days, to complete one Lunation Cycle, from one New Moon to the next.
The Moon's monthly path is inclined to the ecliptic at an angle of about 5°. The points where the Moon's monthly path and the ecliptic intersect are called the Moon's Nodes. The intersection point where the Moon's orbit is travelling from south to north is called the Moon's North Node, or the Dragon's Head, and the intersection point where the Moon's orbit is travelling from north to south is called the Moon's South Node, or the Dragon's Tail.
The Moon's Nodes travel backwards (retrograde) against the order of the Zodiac signs over an 18.6 year period. This is called the Nodal Cycle. There is another significant solar/lunar period which occurs every 19 years within hours known as the Metonic Cycle when the Sun and Moon repeat the same phase, e.g. New Moon, First Quarter, Full Moon, Last Quarter or any phase in between, and when they fall roughly within the same degrees of the Zodiac.
The Lunar Standstill seasons coincide with a time period of roughly 18 and a half years to 19 years and observing the Moon can be of interest for a good 18 months around these standstill seasons.
How do we measure the Sun and Moon north or south of the celestial equator? Declination is measurement north or south of the celestial equator and it is measured from 0? on the celestial equator to 90° + or north, and to 90° - or south of the celestial equator. Declination is the equivalent measurement in space to terrestrial latitude. Celestial Latitude is not the equivalent to terrestrial latitude. It is measurement north or south of the ecliptic, the Sun's apparent annual path as seen from the Earth. The Sun is always at celestial latitude 0° and the Moon can extend to just over 5° north or south of the ecliptic. The Sun and Moon can also be measured in altitude (height above the horizon) but altitude has not been used in this article.
Solar and Lunar Eclipses
A solar or lunar eclipse can only occur when the Sun and Moon are near or on the Moon's Nodes. A solar eclipse occurs at New Moon when the Moon is between the Earth and the Sun. During a solar eclipse the Sun, Moon and Earth are more or less in line on the same celestial latitude. The Moon crosses the face of the Sun causing a shadow to pass over a narrow section of the Earth for a few minutes. A lunar eclipse occurs during Full Moon when the Earth is between the Moon and the Sun. The Earth's shadow crosses the face of the Moon and can be seen taking place for about 3½ hours if it is night time and the weather is clear.
Lunar standstills are in a sense the polar opposites to solar and lunar eclipses. Lunar standstills can never occur during eclipses. During a lunar standstill the Moon has to be roughly at right angles to the Moon's Nodes, instead of being on or near these Nodes. Also the Moon's Nodes have to be in the signs of Aries or Libra, or Virgo or Pisces. These Zodiac signs are near the equinoctial points. The Moon's North Node is in Aries or Pisces during the major lunar standstill season and in Libra or Virgo during the minor lunar standstill season.
Every month the Moon will reach its lowest or highest declination, roughly 28° north or south of the celestial equator, or to express it another way, roughly 5° beyond the ecliptic path. Also every month, the Moon will reach its minimum declination at 18° north or south. The Moon's extremes in declination (or position in relation to the visible horizon) become observable and interesting during the lunar standstill seasons.
The Full Moons throughout the Year
In order to understand lunar standstills, it would also help to describe the Full Moons throughout the year briefly. During the winter months the Full Moon culminates higher and higher in the sky until it reaches its maximum height throughout the year at the full Moon nearest the winter solstice. In the summer months the Full Moon culminates lower and lower in the sky until it reaches its lowest position above the visible horizon at the Full Moon nearest the summer solstice. So the Full Moons nearest the solstices do the opposite to the Sun which is lowest in the sky at the winter solstice and highest in the sky at the summer solstice. Whichever hemisphere you are in, the experience is the same.
What are Lunar Standstills?
Over an 18.6 to 19 year period, the Full Moons nearest the solstices swing much like a pendulum. In 2005 and 2006, these Full Moons will be at their highest and lowest positions in the sky over this approximately 19 year period, reaching declination 28° +/- (north/south). Also the First and Last Quarter Moons around the time of the equinoxes can be seen at their highest and lowest declinations.
In 2015 there will be a minor lunar standstill season, occurring about 9.3 to 10 years after the major lunar standstill season. What occurs now is that the Full Moons nearest the solstices and the First and Last Quarter Moons nearest the equinoxes will reach a minimum declination of approximately 18°+/- (north/south). When this occurs the Full Moon at the winter solstice will be at its lowest in the sky over an approximately 19 year period, while the Full Moon at the summer solstice will be at its highest in the sky over the same period.
If you observed the full Moons nearest the June and December solstices during a major lunar standstill season, you would notice that the height and depth between the two become extreme with an arc of 56° or so. When observing a series of minor lunar standstills you would notice that the height and depth between the two are not so great and less than most full Moons around the solstices with an arc of roughly 36° between the two.
The following is a diagram showing a major and minor lunar standstill of the Full Moon. It has not been drawn to scale, but is a diagram of the tropical regions of the Earth showing the terrestrial latitudes of where the Full Moon is overhead at the standstills in the northern hemisphere. In the southern hemisphere, the Full Moon is south of the Tropic of Capricorn at the major lunar standsill, and north of this Tropic at the minor lunar standstill.
The current series of major lunar standstills occurring in 2005 and 2006 and the next series of minor lunar standstills occurring in 2015 are listed below. The positions of the Moon and nodes have been given to nearest degrees. The dates given are for the exact Full and Quarter Moons, but lowest and highest declination may occur within a day or two of the exact phases.
| Date |
Standstill type |
Full Moon |
North Node |
Dec. |
| 22 Jun. 2005 |
Major south |
1 Capricorn |
20 Aries |
28.11S |
| 15 Dec. 2005 |
Major north |
24 Gemini |
11 Aries |
28.05N |
| 11 Jun. 2006 |
Major south |
21 Sagittarius |
1 Aries |
28.02S |
| 11 Jul. 2006 |
Major south |
19 Capricorn |
29 Pisces |
26.48S |
|
|
Quarter Moon |
|
|
| 17 Mar. 2005 |
Major First Quarter |
27 Gemini |
24 Aries |
28.07N |
| 11 Sep. 2005 |
Major First Quarter |
19 Sagittarius |
14 Aries |
27.42S |
| 25 Sep. 2005 |
Major Last Quarter |
2 Cancer |
14 Aries |
28.35N |
| 10 Oct. 2005 |
Major First Quarter |
18 Capricorn |
14 Aries |
27.31S |
| 6 Mar. 2006 |
Major First Quarter |
16 Gemini |
5 Aries |
27.41N |
| 22 Mar. 2006 |
Major Last Quarter |
2 Capricorn |
4 Aries |
28.43S |
| 5 Apr. 2006 |
Major First Quarter |
16 Cancer |
4 Aries |
27.41N |
| 14 Sep. 2006 |
Major Last Quarter |
22 Gemini |
25 Pisces |
28.26N |
| 30 Sep. 2006 |
Major First Quarter |
7 Capricorn |
25 Pisces |
28.25S |
|
|
Full Moon |
|
|
| 5 Jan. 2015 |
Minor north |
15 Cancer |
15 Libra |
17.41N |
| 2 Jul. 2015 |
Minor south |
10 Capricorn |
5 Libra |
18.05S |
| 25 Dec. 2015 |
Minor north |
3 Cancer |
26 Virgo |
18.26N |
|
|
Quarter Moon |
|
|
| 13 Mar. 2015 |
Minor Last Quarter |
23 Sagittarius |
10 Libra |
18.13S |
| 27 Mar. 2015 |
Minor First Quarter |
6 Cancer |
10 Libra |
18.00N |
| 5 Sep. 2015 |
Minor Last Quarter |
13 Gemini |
1 Libra |
17.20N |
| 21 Sep. 2015 |
Minor First Quarter |
28 Sagittarius |
1 Libra |
18.08S |
The visible Moon, reaching its highest and lowest declination during its First and Last Quarter phases nearest the equinoxes during the major lunar standstill season, seems to have been the part of the cycle that was of most interest to Neolithic peoples. Maybe they were interested in the Full Moon too - it is hard to believe otherwise. A First Quarter Moon rises at noon and sets at midnight. The Last Quarter Moon is visible from midnight and sets at the following noon. It should be noted that these First and Last Quarter Moons are either in the solstice signs of Cancer and Capricorn or in the other signs, nearest the solstice points, Gemini and Sagittarius.
Throughout the major lunar standstill period, the relevant Full Moons lie near the solstice points and the Moon's Nodes are close to the equinox points. A major one north will be followed by a major one south just under 6 months apart. The same applies to the minor lunar standstills.
Major Lunar Standstills and Megalithic Sites
It is believed by some that much emphasis was placed on lunar standstills by the builders of the megalithic sites on the western fringes of Europe and in the British Isles. Perhaps they had an understanding, on some level at least, of the Metonic Cycle (when the Moon reaches the same phase and same degree of the Zodiac every 19 years); the 18.6 year Nodal cycle, the cycle of Eclipses and possibly the Saros cycles. There are at least two eclipse seasons per year. A Saros starts with one Solar eclipse, followed by another one in the same series 18 years, 9 - 11 days later. The Solar eclipses which take place in one year each belong to a different Saros series. A Saros series is made up of roughly 72 Solar eclipses over a 1300 year period.
Some of these megalithic sites are believed to be about 5000 years old, older than the development of astrology and astronomy in the Mesopotamian civilisation and much older than Meton, the Greek (c.430 BCE), who was accredited with the discovery of the Metonic cycle. Robin Heath has explained how the Aubrey holes, the first phase of Stonehenge, were used to predict eclipses and has done much work generally in helping us understand ancient archeoastronomy in relation to stone circles. The 56 Aubrey holes were likely to have been used to predict lunar standstills as well. It is unlikely that the builders understood these cycles in the same way as we do now, but their observations over long periods of time may have enabled accurate predictions of lunar standstills and eclipses. Considering that Neolithic people did not live very long lives, this would have been an amazing achievement and knowledge must have been passed on from parent to child.
The lunar standstills, whether they were being observed during the Quarter or Full Moon phases, were apparently prominent events observed from some stone rows, such as the Merrivale Stone Row on Dartmoor in the south west of England, from stone rows on the Isle of Mull off the west coast of Scotland and at Temple Wood stone circle near Kilmartin in Argyle. Other examples are rings of standing stones west of Aberdeen, Scotland. There are many others throughout the western fringes of Europe. The combination of stones and prominent hill tops, with their notches, were one of the major ways Sun and Moon positions were noted at significant times.
The Callanish stones, at latitude 58.12 north, are famous for picking up the lunar standstills at their most southerly positions against the hills on the horizon. There is about five hours of darkness in midsummer. It is worth pointing out too that at this latitude during the major lunar standstills north the Moon hardly sets. You can observe these standstills from anywhere although it would be better to be in the country with a good view.
According to Service and Bradbery in their book, The Standing Stones of Europe, in the Shetland Islands at latitude 60 plus north, the major lunar standstills north become circumpolar, never rising nor setting. Because the Earth's axial tilt has changed by nearly half a degree since the majority of stone circles were built, the circumpolar Moon was visible in the Shetlands in neolithic times. It is not quite circumpolar today - according to the formula in Philip's Astronomy Dictionary - polar distance of 90° less Moon's declination should be less than the observer's latitude for the Moon to become circumpolar. Result is 62° - 2° out. So terrestrial latitude would have to be 63° north for a lunar standstill north to be truly circumpolar today. The reverse would be the case in the southern hemisphere.
Summary
What I have tried to do in this article is to show how the lunar standstills are part of a whole cycle of the Moon, in its fullness and quarter phases over an 18.6 to 19 year period. I have not given dates when the Moon is literally at its lowest or highest declination as I do not have software adequate enough to find these exact dates and time quickly.