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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 1º a day, taking
365 days to complete one cycle.
The Earth is tilted on its axis at an angle of 23º. 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
8º north and south of the ecliptic and the Tropical Zodiac starts
from 0º 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 30º 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 0º 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 0º Libra. It is mid
autumn in the northern hemisphere and mid spring in the southern
hemisphere.
On about 22 December, the Sun enters 0º Capricorn and is overhead
the Tropic of Capricorn at terrestrial latitude 23º 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 0º
Cancer and is overhead the Tropic of Cancer at terrestrial latitude
23º 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 27 days to orbit the Earth and to travel round
the Zodiac from Aries to Pisces. The Moon takes a little longer,
about 29 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 5º. 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 0º on the celestial equator to 90º
+ or north, and to 90º - 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 0º and the Moon can extend to just over 5º 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 3 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 28º north or south of the celestial equator, or to express
it another way, roughly 5º beyond the ecliptic path. Also every
month, the Moon will reach its minimum declination at 18º 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 28º +/- (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 18º+/- (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.
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.
© Jean Elliott, DFAstrolS., RCAstrol., 2005.
Jean works as an astrologer in Leominster, Herefordshire (www.starwaves.co.uk)
and is a Director of astrologycollege.com which provides correspondence
courses (distance learning) in astrology from beginners to advanced
level (www.astrologycollege.com). astrologycollege.com is a member
of the Astrological Guild of Educators International (www.theastrologicalguild.co.uk).
Jean is also involved in the Wheel of Astrologers, a group of
friends united by a love of astrology who hold outdoor gatherings
and camps and work at outdoor events such as Glastonbury Festival
and the Big Green Gathering (www.wheelofastrologers.co.uk).
References:
The Stars and The Stones. Ancient Art and Astronomy in Ireland.
Martin Brennan. Thames & Hudson 1983. Now under a different
title: The Stones of Time, Calendars, Sundials and Stone Chambers
of Ancient Ireland. Inner Traditions 1995.
Sun, Moon and Stonehenge. Proof of High Culture in Ancient Britain.
Robin Heath. Bluestone Press. 1998. Copies available from Robin
at Bluestone Press, tel: 01239 613224.
The Secret Language of the Stars and Planets. A Visual Key to
the Celestial Mysteries. Geoffrey Cornelius and Paul Devereux.
Duncan Baird Publishers. 1997.
Prehistoric Astronomy and Ritual. Aubrey Burl. Shire Archaeology.
1983.
The Standing Stones of Europe, A Guide to the Great Megalithic
Monuments. Alastair Service and Jean Bradbery. Weidenfeld &
Nicolson. London. 1996 edition.
Astronomy Before the Telescope. Editor, Christopher Walker. British
Museum Press. 1999 edition. Chapter on Archeoastronomy in Europe
by Clive Ruggles.
The Eagle and the Lark, A textbook of predictive astrology, Bernadette
Brady, Samuel Weiser Inc. 1992. Gives detailed information on
the Saros series of eclipses and explains their astronomy.
Solar Fire v5.
American Ephemeris for 20th and 21st Centuries.
Diagram by Tina Smale of Ethix Design (www.ethixdesign.co.uk).
Acknowledgements:
Thanks to Robin Heath, Tchenka, Dave Baker, Lyn Lovell and Linda
Walton for putting me on the right track. Thanks also to Robin
Heath for checking the original article I wrote for the Astrological
Journal in the November/December issue 2002 published by The Astrological
Association of Great Britain. Thanks also to Gerald Ponting for
his article on ‘The Southern Moon Skim’ at Callanish
2006, Southern Extreme of the Major Standstill.
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