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HORUS VOL II. Issue 3
Setting And Using The Stonehenge
|Days in June||9|
|Days in July||22|
Since 36 days X 2 holes per day = 72 holes, the marker will move around the Sun Circle one time plus eight days (16 holes) and will rest on the second hole below the quarter
axis near B (Figure 1). This point represents July 27th in the solar year.
The calendar has now been "set" to the correct Sun and Moon time for 27 July 1985 and is ready to operate as an astronomical "clock."
From this point the Sun marker is moved clockwise two holes per day and the Moon marker is moved clockwise one space per day, switching every other revolution from the 30 to the 29-day Lunar Circle, and back, as indicated by the crossed arrows.
Because of the fractional values of the solar year and the lunar month, intercalations and slight adjustments, as determined by visual observation, will have to be made periodically with the markers to keep the "hands" of the calendar in accurate synchronization with these two celestial bodies. At Stonehenge, the month of the year is determined by noting the azimuth of sunrise and whether the Sun is moving North or South.
[*!* Image: Figure 1. Setting the Sun and Moon Markers. LABELS: Winter Solstice; Summer Solstice; Autumn Equinox; Spring Equinox; Heelstone Axis; Sunrise; Horizon; Spring; Winter; Summer; Autumn].
The two markers eventually will come into conjunction (be radially aligned) on the Heelstone and quarter axes at four specific times during the 19-year solar-lunar cycle as follows:
Year 0; At Winter solstice and Full Moon, both markers are on the Heelstone axis, the. Sun marker near A, and the Moon marker near hole #8 of the Lunar Circles. [Figure 2.]
[*!* Image: Figure 2. Marker positions at Winter solstice and Full Moon. LABELS: Winter Solstice; Summer Solstice; Autumn Equinox; Spring Equinox; Heelstone Axis; Sunrise; Horizon; Spring; Winter; Summer; Autumn].
[*!* Image: Figure 3. Marker positions at Fall Equinox amd first quarter of the Moon. LABELS: Winter Solstice; Summer Solstice; Autumn Equinox; Spring Equinox; Heelstone Axis; Sunrise; Horizon; Spring; Winter; Summer; Autumn].
Year 4-3/4 (first quarter of the cycle): At Fall Equinox and the first quarter of the Moon, both markers lie along the quarter axis, the Sun marker near B, and the Moon marker near hole # 1 of the Lunar Circles. [Figure 3.]
Year 9-1/2 (midpoint of the cycle); At Summer solstice and New Moon, both markers are on the Heelstone axis, the Sun marker near C and the Moon marker between holes #22 and #23 of the Lunar Circles. [Figure 4.]
Year 14-3/4 (third quarter of the cycle); At Spring equinox and the last quarter of the Moon, both markers are along the quarter axis, the Sun marker near D and the Moon marker near hole #15 of the Lunar Circles. [Figure 5.]
[*!* Image: Figure 4. Marker positions at Summer solstice and New Moon. LABELS: Winter Solstice; Summer Solstice; Autumn Equinox; Spring Equinox; Heelstone Axis; Sunrise; Horizon; Spring; Winter; Summer; Autumn].
[*!* Image: Figure 5. Marker positions at Spring equinox and the last quarter of the Moon. LABELS: Winter Solstice; Summer Solstice; Autumn Equinox; Spring Equinox; Heelstone Axis; Sunrise; Horizon; Spring; Winter; Summer; Autumn].
Year 19 (end of the cycle); At Winter solstice and Full Moon, both markers again are on the Heelstone axis, the Sun marker near A, and the Moon marker near hole #8 of the Lunar Circles. [Figure 2.]
It will be seen that the fifth conjunction duplicates the first and thus indicates the end of one 19-year cycle and the start of the next. Since the described operation is cyclic (endlessly repeats itself), the start of the cycle can be set arbitrarily at my point within the 19-year period, just as you would set your watch. Since the two Lunar Circles contain a clear and obvious gap at the first quarter point of the lunar month (on the Heelstone axis near B) it would appear that the calendar designers intended this as the beginning point of their months, that is, at first quarter of the Moon. I suggest this as the starting point of the year and the 19-year cycle as well: more specifically; at Sunset, at the first quarter of the Moon, eight days before the Winter solstice.
The conjunctions delineated above will occur at the times and in the same sequence as indicated, and will continue to do so every 19 years.
Note that as the Moon marker moves around the Lunar Circles, its position on those circles accurately indicates the Moon's actual phases as represented just inside the Sarsen Circle.
Note also that the Trilithons, by the alternate increase and decrease in their heights from New Moon (where there is no Trilithon at all) to Full Moon phase as symbolized by the largest Trilithon of all (The Great Trilithon) when the Moon marker stone is adjacent to that element, and then waning back to New Moon through the two smaller Trilithons, which figuratively represent the monthly waxing and waning of the Moon.
When the Sun and Moon markers are in conjunction on the Heelstone axis near A with the Moon at full at Winter solstice, the Sun will actually set along that Heelstone axis as viewed through the Great Trilithon from the center of the site while, about the same time, the Full Moon will rise near the Heelstone (the setting Winter solstice Sun on the western horizon, with the Full Moon rising on the eastern horizon). [Figure 2.]
When the Sun and Moon markers are in conjunction on the Heelstone axis near C with the Moon at New, at Summer solstice, both the Sun and New Moon (invisible) will rise together along that Heelstone axis near the Heelstone. [Figure 3.]
This mode of operation assumes seasons of equal length. However, since Spring and Summer are each about four days longer than Autumn or Winter, the Sun marker will not be on the quarter axis at the time of Spring and Autumn equinoxes, but will be two days (four holes) from that axis. In actuality, the Sun marker will be four holes below the axis at Spring equinox at that part of the Sun Circle conventionally known as "Station 93". The marker will be four holes below the axis at Autumn equinox at that point of the Sun Circle conventionally known as the "South Mound." Of course, at both these times in the solar year the Sun will rise and set nearly due East and West.
As indicated above, the Stonehenge calendar needed to be reset from time to time to keep it in step with the Moon and the Sun. How was this done? Most lunar-solar calendars had months that began on the day when the first thin sliver of the New Moon became visible in the western sky. Being very close to the Sun in the New Moon phase, this slender lunar crescent usually can not be seen until the bright solar orb has dropped below the horizon. Since the time between first sighting of the crescent and its descent behind the rim of the earth is not very great - perhaps a half an hour or so - this fact posed a bothersome observational problem, since clouds, mist, or horizon haze often obscures the event entirely. In most cases, the people who used this type of calendar learned to live with the problem. In some instances the start of the month was changed to the time of the Full Moon. This increased the time of observation considerably, since the Full Moon can be in the sky for as much as 12 hours or more, but this did little to eliminate the basic difficulty. The Moon seldom becomes totally full during the so-called Full Moon phase; instead, it exhibits a thin dark crescent on its northern edge. (At those rare times when it does become totally full, it will suffer an eclipse.) At any given sighting of the "Full Moon", the question persists as to whether it will be fuller the following night, and pinpointing the exact day of the exact day of Full Moon becomes an educated guess.
Celtic astronomers, who were noted in the ancient world for their extensive knowledge of celestial matters, ingeniously solved the problems by having their months begin at the first quarter of the Moon. At this time the Moon's terminator (the line separating the light and dark areas) appears to naked eyes as though it were drawn with a straight edge. On both preceding day and on the following day there is a pronounced, easily observed bow in the terminator.
Also, since at first quarter phase the Moon is about 90 degrees east of the Sun, it will be above the horizon for half a day or more, thereby greatly increasing the chance of being observed at some time during the day, even though it is mostly cloudy.
For further reading; The Old Farmer's Almanac, available at any news stand, contains data on the phases of the Moon which are prepared by a professional astronomer. "How Young a Moon Can You See?", by Chet Raymo (1985, p. 39) gives some clues on the sport of looking for very young or very old Moons.
Alban Wall is a graduate of the United States Merchant Marine Academy. In addition to his career as a mariner, he was an instructor in the Department of Navigation and Seamanship, U.S. Merchant Marine Academy. He also has served as a Lt. Commander, USNR. Mr. Wall has published several articles in KRONOS, as well as HORUS, on the subject of Stonehenge and other areas related to archaeoastronomy. He has published other contributions in Reader's Digest. Look for a further work on the Coligny Calendar in a future issue of HORUS.