ANNOUNCEMENTS 1. HOMEWORK #3 WILL BE HANDED OUT THURSDAY; DUE FOLLOWING THURSDAY. HW #@ due this Thursday at class. HW CLUB THIS WEEK AS USUAL 2. OBSERVING SESSIONS: THIS THURS NIGHT AT SBO AT 8pm 3. SUNDIAL HELP SESSION Tomorrow after HW Club (1pm and 3pm) with Kate Vann 4. BOOKS AND SKY GAZER PROGRAM DISKS NEEDED FOR OBSERVING PROJECTS NOW ON RESERVE ACROSS THE HALL IN THE GEOLOGY LIBRARY. 4. Note taker position filled THANKS to all that responded. Ms Sheevam and Mr Russum please see me after class. UP FOR DISCUSSION TODAY: THE MERIDIAN SLICE, SOLAR CALENDARS & SOLSTICE MARKERS.
AT MID-LATITUDES: calendars set by SUN ON HORIZON OR SUN ON MERIDIAN *** angle Sun takes across sky = latitude CHANGES LOCATION SIGNIFICANTLY TH AT LOW LATITUDES (i.e., in the TROPICS) THE SUN S HORIZON LOCATION CHANGES LESS AND ALTITUDE ALONG MERIDIAN CHANGES VERY LITTLE
WINTER SOLSTICE SUN MOVES ACROSS THE SKY IN SOUTHERN GREECE ANGLE SUN LEAVES HORIZON = 90 O LATITUDE MORE HORIZONTAL AT HIGHER LATITUDES HORIZON MARKERS MORE EFFECTIVE because SOLSTICE MARKERS ARE SPREAD FARTHER APART
EAST-WEST IS THE DIMENSION OF TIME IN THE SKY
INTRODUCING THE MERIDIAN SLICE : A SLICE THROUGH THE CELESTIAL SPHERE ALONG THE MERIDIAN LOCATION OF THE SUN AT SOLAR NOON, ALTHOUGH ITS POSITION ALONG THIS SLICE OF THE SPHERE CHANGES DURING THE SEASONS. WHICH IS THE CAUSE OF THE SEASONS COMMENTS ON A PRIVATE UNIVERSE
DOES THE SUN EVER GO THROUGH THE ZENITH HERE IN BOULDER?
23 ½ -23 ½ THE SOLAR ZONE the range of altitudes which the Sun exhibits along the meridian during the year.
CHINESE SKY MEASURING SCALE: a meridian line LOCATES POSITION OF SUN ALONG THE MERIDIAN AT SOLAR NOON. LOCATION ALONG THE SCALE SETS THE SEASONAL CALENDAR LATITUDE = 34.5 O N ARROW INDICATED THE SOLAR ZONE ANGLES IN THE SKY WHERE SUN IS SEEN
CENTER OF THE SOLAR ZONE IS ALWAYS AT THE CELESTIAL EQUATOR EVERYWHERE ON EARTH. HENAN PROVINCE, CHINA 34.5 90 34.5 = 55.5 34.5
THE MERIDIAN SLICE Has the Celestial Latitude = terrestrial latitude @ the zenith Basis of celestial navigation to determine one s LATITUDE. Measure the altitude of the meridian passage of fixed stars; i.e., fixed celestial latitudes *** WHERE ARE THE SOLAR ZONES FOR KEY WEST & THE EQUATOR?
IN THE TROPICS AT LATITUDES < 23 ½ DEGREES, THE SUN GOES THROUGH THE ZENITH TWICE PER YEAR. THE MERIDIAN SLICE Has the Celestial Latitude = terrestrial latitude @ the zenith Basis of celestial navigation to determine one s LATITUDE. Measure the altitude of the meridian passage of fixed stars; i.e., fixed celestial latitudes
IN THE TROPICS AT LATITUDES < 23 ½ DEGREES, THE SUN GOES THROUGH THE ZENITH TWICE PER YEAR. THE MERIDIAN SLICE Has the Celestial Latitude = terrestrial latitude @ the zenith Basis of celestial navigation to determine one s LATITUDE. Measure the altitude of the meridian passage of fixed stars; i.e., fixed celestial latitudes
THE SOLAR ZONE: Winter solstice on December 21 st Summer or winter makes little difference Summer solstice on December 21 st AT ANY ONE LOCATION THIS IS THE FULL RANGE OF LOCATIONS ALONG THE MERIDIAN WHERE THE SUN CAN BE SEEN DURING THE YEAR. IN EITHER HEMISPHERE THE SOLAR ZONE LOCATES THE SUMMER (HIGHEST ALTITUDE EDGE OF SOLAR ZONE) AND WINTER SOLSTICES. THE EQUINOX POSITIONS ARE HALFWAY BETWEEN THESE TWO EXTREMES.
CHINESE SKY MEASURING SCALE: a meridian line LOCATES POSITION OF SUN ALONG THE MERIDIAN AT SOLAR NOON. LOCATION ALONG THE SCALE SETS THE SEASONAL CALENDAR LATITUDE = 34.5 O N ARROW INDICATED THE SOLAR ZONE ANGLES IN THE SKY WHERE SUN IS SEEN
A PARTIAL SOLAR ECLIPSE AS OBSERVED CROSSING THE MERIDIAN LINE AT SANTA MARIA DEGLI ANGELI (near the train station, Roma Termini, in downtown Rome, Italy). The numbers to the right of the Meridian Line tell us that the eclipse happened on the 79 th day of the year; i.e., the meridian line is a calendar. Altitude of the Sun calibrated only along the meridian, when it is at its highest point each day. Meridian line effect only seen for ~ 30 minutes around Solar Noon
The Tower of the Winds 1576 18
Tower of the Winds South Wall 19
Gregorian Calendar Reform (1582) POPE GREGORY USED THE TOWER OF THE WINDS IN THE VATICAN TO GREET EUROPEAN HEADS OF STATE And THE MERIDIAN LINE HELPED HIM CONVINCE THESE HEADS TO CONVERT THEIR COUNTRY TO THE NEW CALENDAR. 20
THE SOLAR CALENDAR: BUSINESS TIME THE PROBLEM: CALENDAR MAKERS WANTED TO INCOPRORATE THE CYCLES OF BOTH THE SUN AND THE MOON but 12 X 29.5 DAYS IN THE LUNAR MONTH = 354 DAYS 11 ¼ DAYS SHORT. THE SOLUTION IS CALLED INTERCALATION to add or subtract days or months to keep on the schedule of the Sun and Moon or on the schedule of just one of these. BABYLONIAN/GREEK SOLUTION WAS TO KEEP BOTH SUN AND MOON CYCLES AND INTER- CALATE BY ADDING AN ENTIRE 13 TH MONTH ON A 2 3 YEAR SCHEDULE OVER 19 YEARS ( YEAR of METON )). EGYPTIAN SOLUTION WAS TO ABANDON LUNAR CYCLE ALTOGETHER SO THAT THE YEAR WAS ALWAYS THE SAME NUMBER OF DAYS (365) AND MONTHS (12), but the MONTHS HAD > 29 DAYS.
THE JULIAN CALENDAR THE EGYPTIAN SOLUTION (c. 300 BCE) WAS TO ABANDON THE LUNAR CYCLE AND CREATE A PURE SOLAR CALENDAR OF 12 X 30 DAY MONTHS + 5 FEAST DAYS. ADOPTED BY ROME IN 45 BCE AFTER THE YEAR OF CONFUSION (46 BCE WHICH HAD 465 DAYS TO CORRECT FOR PAST MISTAKES). LEAP YEARS WERE ADDED AT THAT TIME. EVERY YEAR WHOSE NUMBER IS EVENLY DIVISIBLE BY 4 HAS 366 DAYS.EXTRA DAY ADDED TO February, the last month of the year WHEN ROME BECAME THE POLITICAL AND MILITARY POWER IN EUROPE THE LUNAR CYCLE WAS ABANDONED IN FAVOR OF THE EGYPTIAN SOLAR CALENDAR. JULIAN CALENDAR started in March. Thus, e.g., October is 8 th month (not 10 th as currently) and February was the last month of the year. Originally months alternated 30 and 31 days but Julius & Augustus stole days from Feb. for their months,.
GREGORIAN CALENDAR (c. 1600 TO PRESENT) THE YEAR IS ACTUALLY ~ 11 MINUTES SHY OF 365 ¼ DAYS LONG. OVER NEARLY 1600 YEARS THIS DISCREPANCY CAUSED THE JULIAN CALENDAR TO BE OFF BY 10 DAYS. EASTER WAS HAPPENING IN WARMER AND WARMER WEATHER POPE GREGORY COMMISIONED A STUDY TO CHANGE THE CALENDAR SOLUTION OF ALYOSIUS LILIO ADOPTED CENTURY YEARS NOT DIVISIBLE BY 4 ARE NO LONGER LEAP YEARS. BY 1600s THE CLERGY NOTICED THAT EASTER WAS SLOWLY BECOMING A WARM-WEATHER SUMMERTIME FESTIVAL, NOT THE SPRING REBIRTH SYMBOLICALLY REQUIRED POPE GREGORY WAS CONVINCED TO CHANGE THE CALENDAR AND HE GOT CATHOLIC COUNTRIES TO CHANGE BUT NOT THE PROTESTANT ONES e.g., BRITAIN DID NOT CHANGE UNTIL 1700s.; Russia in 1900s.
THE FOUR CORNERS OF THE YEAR : SOLSTICES AND EQUINOXES MARCH 20 OR 21 st : SPRING OR VERNAL EQUINOX ( EQUAL NIGHT TO DAY ) JUNE 21 ST : SUMMER SOLSTICE OR MIDSUMMER {solstice means Sun standing still (on horizon as it sets)} SEPTEMBER 21 st OR 22 nd : FALL EQUINOX DECEMBER 21 st : WINTER SOLSTICE SOLSTICES: SUN IS AS FAR NORTH OR AS FAR SOUTH AS SUN CAN GET: CELESTIAL LATITUDE = + 23½ o AND 23 ½ o. EQUINOXES: SUN IS ON THE CELESTIAL EQUATOR (Celestial latitude = 0). DAY & NIGHT OF EQUAL LENGTH OF TIME. LATITUDE =+23½ O IS CALLED THE TROPIC OF CANCER and LATITUDE =-23½ O IS CALLED THE TROPIC OF CAPRICORN IN BETWEEN THESE LATITUDES ARE THE TROPICS.
CELESTIAL LATITUDE OF SUN THROUGH THE YEAR SOLSTICES AND EQUINOXES IN GREEN RED MARKS SHOW APPROXIMATE LOCATIONS OF CROSS-QUARTER DAYS NOTE TWO SUNS PHENOMENON: SUN STAYS CLOSE TO SAME TWO LOCATIONS IN SKY OVER MUCH OF YEAR: SUMMER SUN AND WINTER SUN Time of changes SUMMER SUN Winter Sun Winter Sun CONTINUES
THE CELTIC CROSS-QUARTER DAYS: THE TRADITIONAL DIVISION OF THE SEASONS: AUTUMN EQUINOX: SEPT 21 22 (+42 days) NOV 1 st SAMHAIN (Halloween) (+50 days) WINTER SOLSTICE: DEC 21 ST (+43 days) IMBOLG OR CANDELMAS FEB 2 nd (GROUNDHOG DAY) (+46 days) SPRING EQUINOX MAR 20-21 (+42 days) BELTANE: MAY 1 st (May Day) (+50 days) SUMMER SOLSTICE : JUNE 21 st (+42 days) LAMMAS (or LUGHNASH): AUG 2 nd ANCIENT TRADITION IS THAT FIRST DAYS OF SEASONS ARE THE CROSS QUARTER DAYS.. e.g., BELTANE (May Day) is the FIRST DAY OF SUMMER. June 21 st, the Summer Solstice is also called HIGH OR MID- SUMMER.
CELESTIAL LATITUDE OF THE SUN THROUGH THE YEAR SOLSTICES AND EQUINOXES IN GREEN TAURUS GEMINI ARIES CANCER PISCES AQUARIUS CAPRICORN SAGITTARIUS LEO VIRGO LIBRA SCORPIO CONTINUES CONSTELLATIONS OF THE ZODIAC ARE DISTRIBUTED ALONG THE ECLIPTIC (PURPLE LINE ABOVE) IN THE SKY
THE 4 CORNERS OF THE YEAR: SOLSTICES AND EQUINOXES SOLSTICE MARKERS ARE A WORLD-WIDE PHENOMENON THAT STRETCHES WAY BACK INTO TIME.. FOR EXAMPLE, SOLSTICES: SUN STANDING STILL. SUN RISES AND SETS AT ALMOST EXACTLY THE SAME LOCATIONS FOR APPROXIMATELY 2 WEEKS AROUND THE SOLSTICES EQUINOXES: EQUAL NIGHT TO DAY. SUN RISES AND SETS DUE EAST AND WEST AND SO STAYS UP FOR 12 HOURS AND IS DOWN FOR 12 HOURS.
SOLSTICE MARKERS ARE A WORLD-WIDE PHENOMENON: OLDEST KNOWN SOLSTICE MARKERS IN THE WORLD: CIRCA 5000 BCE IN SOUTHERN EGYPT. Site mapped by CU Professor Emeritus Kim Malville. ** SHOW VIDEO: COSMIC AFRICA **
NEWGRANGE IN IRELAND A 5000+ YEAR OLD PASSAGE TOMB ALIGNED TO WINTER SOLSTICE SUNRISE ONLY AT THE WINTER SOLSTICE SUNRISE IS THE INNERMOST CHAMBER OF THIS PASSAGE TOMB ILLUMINATED BY THE SUN. An obvious symbol of rebirth, of the year and so of humans.
STONEHENGE: EARLIEST ASTRONOMICAL CONSTRUCTION C. 3200 BCE.
WINTER SOLSTICE SUNSET
KINTRAW WINTER SOLSTICE MARKER: COUNTY Argyll, Scotland
COLOSSI OF MEMNON TEMPLE OF AMENHOTEP III AT THEBES ALIGNED WITH WINTER SOLSTICE SUNRISE!!
TEMPLE OF AMENHOTEP III circa 1350 BCE (1200 YEARS AFTER THE GREAT PYRAMIDS AT GIZA SUN WORSHIP REPLACED OSIRIS BITRTH/DEATH/ REBIRTH CULT SOLAR COURTYARD ILLUMINATED ONLY AT WINTER SOLSTICE DAWN!
SETTING CALENDARS BY THE SUN THE SUNDAGGER EFFECT ON MIDSUMMER S DAY AT NOON IN CHACO CANYON, NM mid- Winter also marked!!
MACHU PICCHU HIRAM BINGHAM 1913 WINTER SOLSTICE SUNRISE
INTI RYMI: THE LARGEST SOLSTICE CELEBRATION IN THE WORLD! At Cusco in Peru.
QUESTION: WHY WOULD THE WINTER SOLSTICE BE THE ONE WHICH IS MOST CELEBRATED BY ANCIENT PEOPLES? 1. IT MARKS THE RETURN OF THE LIGHT 2. LESS DAYLIGHT FOR WORKING, MORE TIME FOR PARTYING. 3. IT S A SILLY, PAGAN THING. 4. AT THE WINTER SOLSTICE, THE DARKNESS OVERWHELMS THE LIGHT. IT S AN EVIL TIME. 5. SOME ANCIENT PEOPLES WERE WORRIED THAT THE SUN WOULD KEEP GOING SOUTH AND STAY THERE.
QUESTION: WHY WOULD THE WINTER SOLSTICE BE THE ONE WHICH IS MOST CELEBRATED BY ANCIENT PEOPLES? 1. IT MARKS THE RETURN OF THE LIGHT 2. LESS DAYLIGHT FOR WORKING, MORE TIME FOR PARTYING 3. IT S A SILLY, PAGAN THING. IN THE OLD ROMAN CALENDAR THE WINTER SOLSTICE WAS ON DECEMBER 25 th AND WAS CALLED THE DAY OF THE UNCONQUERABLE SUN! CHRISTIANS CO-OPTED IT. 4. AT THE WINTER SOLSTICE, THE DARKNESS OVERWHELMS THE LIGHT. IT S AN EVIL TIME.
Tuesday s class ended here
WINTER SOLSTICE SUNSET
HORIZON CALENDAR: requires both a foresight (typically point on horizon) and backsight (location or stone marker) { see Observing Project #2} HOPI of ARIZONA USE A HORIZON, SUNSET CALENDAR TO SET THEIR WINTER SOLSTICE CEREMONY THE SOYAL.
5). HELIACAL RISING OF CERTAIN KEY STARS (SIRIUS/SOTHIS, PLEIADES) METHODS FOR SETTING A SOLAR CALENDAR 1). RISING OR SETTING POINTS OF THE SUN ALONG THE HORIZON {HOPI, EGYPTIAN, CELTS, etc etc} 2) SHADOW OF A GNOMON (VERTICAL STICK) or PINHOLE IMAGE OF THE SUN ALONG A MERIDIAN LINE {EGYPTIAN, CHINESE, EUROPEAN} 3). ZENITH PASSAGE DAYS = THE TWO DAYS PER YEAR THAT THE SUN GOES EXACTLY THROUGH THE ZENITH IN THE TROPICS (-23.5 O TO + 23.5 O ) 4). DAY THE SUN FIRST BREAKS THE HORIZON IN THE FAR NORTH We ll take these one-by-one. ALL WERE USED BY ANCIENT PEOPLE BUT TRADITION DIFFERED IN DIFFERENT LOCATIONS AND CULTURES.
5). HELIACAL RISING OF CERTAIN KEY STARS (SIRIUS/SOTHIS, PLEIADES) METHODS FOR SETTING A SOLAR CALENDAR 1). RISING OR SETTING POINTS OF THE SUN ALONG THE HORIZON {HOPI, EGYPTIAN, CELTS, etc etc} 2) SHADOW OF A GNOMON (VERTICAL STICK) or PINHOLE IMAGE OF THE SUN ALONG A MERIDIAN LINE {PUEBLO, EGYPTIAN, CHINESE, EUROPEAN} 3). ZENITH PASSAGE DAYS = THE TWO DAYS PER YEAR THAT THE SUN GOES EXACTLY THROUGH THE ZENITH IN THE TROPICS (-23.5 O TO + 23.5 O ) 4). DAY THE SUN FIRST BREAKS THE HORIZON IN THE FAR NORTH We ll take these one-by-one. ALL WERE USED BY ANCIENT PEOPLE BUT TRADITION DIFFERED IN DIFFERENT LOCATIONS AND CULTURES.
NOTES ON INTERCALATING: JULIAN CALENDAR (45 BCE) had leap years every 4 years an extra day added to February (last month of year). BUT that was too much by a tiny bit *** OVER 16 centuries the 11 minutes discrepancy added up to about 2 weeks that had to be dropped from the calendar to bring it back to concurrence with the Sun GREGORIAN CALENDAR (c. 1600 CE) has leap years on century years only if the century number is evenly divisible by 4 ATOMIC TIME : TODAY WE KEEP THE GREGORIAN CALENDAR BUT ADD OR SUBTRACT LEAP SECONDS TO THE ATOMIC CLOCKS TO KEEP THEM IN STEP WITH THE MOTION OF THE SUN. BUT IF A CULTURE WANTED TO KEEP TRUE TO BOTH THE SEASONS (i.e., the Sun, Male Energy) AND THE LUNAR PHASES (i.e., the Moon, Female Energy) THEY NEEDED TO INTERCALATE WITH WHOLE MONTHS EACH 2 OR 3 YEARS since the 365 ¼ day Solar Year is not an even number of lunar phase cycles of 29 ½ days. { 29.5 x 12 = 354 days, 11+ days short!)
METHODS FOR SETTING A SOLAR CALENDAR 1) SHADOW OF A GNOMON (VERTICAL STICK) or PINHOLE IMAGE OF THE SUN ALONG A MERIDIAN LINE {EGYPTIAN, CHINESE, EUROPEAN} 2) RISING OR SETTING POINTS OF THE SUN ALONG THE HORIZON {HOPI, EGYPTIAN, CELTS, etc etc} 3). ZENITH PASSAGE DAYS = THE TWO DAYS PER YEAR THAT THE SUN GOES EXACTLY THROUGH THE ZENITH IN THE TROPICS (-23.5 O TO + 23.5 O ) ALL WERE USED BY ANCIENT PEOPLE BUT TRADITION DIFFERED IN DIFFERENT LOCATIONS AND CULTURES. 4). DAY THE SUN FIRST BREAKS THE HORIZON IN THE FAR NORTH 5). HELIACAL RISING OF CERTAIN KEY STARS (SIRIUS/SOTHIS, PLEIADES)
QUESTION: WHERE ON EARTH DOES THE SUN GO DIRECTLY OVERHEAD ON DECEMBER 21 ST? A). No where. This is Midwinter and the Sun is very low in the sky everywhere. B). The equator, latitude = 0 o C). The Tropic of Capricorn, latitude = -23½ o D). Greenwich, England, the prime meridian E). The Tropic of Cancer, latitude = +23½ o F). Everywhere.
QUESTION: WHERE ON EARTH DOES THE SUN GO DIRECTLY OVERHEAD ON DECEMBER 21 ST? A). No where. This is Midwinter and the Sun is very low in the sky everywhere. B). The equator, latitude = 0 o C). The Tropic of Capricorn, latitude = -23½ o midsummer in the southern hemisphere D). Greenwich, England, the prime meridian mid- E). The Tropic of Cancer, latitude = +23½ o winter in the northern hemisphere F). Everywhere.
THE SOLAR ZONE: Winter solstice on December 21 st Who cares? Summer solstice on December 21 st AT ANY ONE LOCATION THIS IS THE FULL RANGE OF LOCATIONS ALONG THE MERIDIAN WHERE THE SUN CAN BE SEEN DURING THE YEAR. IN EITHER HEMISPHERE THE SOLAR ZONE LOCATES THE SUMMER (HIGHEST ALTITUDE EDGE OF SOLAR ZONE) AND WINTER SOLSTICES. THE EQUINOX POSITIONS ARE HALFWAY BETWEEN THESE TWO EXTREMES.
THE YEAR IN THE TROPICS SEASONAL YEAR NOT AS CRITICAL TO MEASURE ACCURATELY. LENGTHS OF DAYS AND NIGHTS DO NOT VARY SIGNIFICANTLY OVER THE YEAR AND THE SUN S RISING AND SETTING POINTS DO NOT CHANGE SO MUCH DURING THE YEAR AS AT MID- LATITUDES. BETWEEN THE TROPICS OF CANCER AND CAPRICORN THE SUN ATTAINS THE ZENITH AT NOON TWO DAYS PER YEAR. THESE ZENITH PASSAGE DAYS ARE LISTED IN THE NOTES ON PAGE 51. ZENITH PASSAGE DAYS CAN BE USED TO SET A SEASONAL CALENDAR ACCURATELY..BUT ONLY IN THE TROPICS. IF SOMEONE COULD DETERMINE WHEN THE SUN GOES EXACTLY THROUGH THE ZENITH.
Eratosthenes of Cyrene Michael Lahanas Ερατοσθένης ο Κυρηναίος : Μέτρηση μήκους περιφέρειας της γης WELL OF SYENE IN EGYPT EXACTLY ON TROPIC OF CANCER 23½ DEGREES NORTH LATITUDE
MAYA TIMES and PLACES IN THE NEW WORLD THE MAYA PEOPLE LIVE IN THE TROPICS & ARE THE GREATEST CALENDAR MAKERS OF ALL LATITUDE =14.5 N COPAN, HONDURAS CITY THAT MADE EARLY MAYA CALENDARS
AT MONTE ALBAN SUN REFLECTS IN POOL OF WATER
XOCHICALCO
CENOTES, SACRED WELLS, ABOUND IN THE YUCATAN. HERE ARE A COUPLE AROUND CHICHEN ITZA BELOW IS AN EXAMPLE OF THE ZENITH SUN EFFECT (AUG 2013 NATIONAL GEO)
METHODS FOR SETTING A SOLAR CALENDAR 1) SHADOW OF A GNOMON (VERTICAL STICK) or PINHOLE IMAGE OF THE SUN ALONG A MERIDIAN LINE {EGYPTIAN, CHINESE, EUROPEAN} 2) RISING OR SETTING POINTS OF THE SUN ALONG THE HORIZON {HOPI, EGYPTIAN, CELTS, etc etc} 3). ZENITH PASSAGE DAYS = THE TWO DAYS PER YEAR THAT THE SUN GOES EXACTLY THROUGH THE ZENITH IN THE TROPICS (-23.5 O TO + 23.5 O ) 4). DAY THE SUN FIRST BREAKS THE HORIZON IN THE FAR NORTH We ll take these one-by-one. ALL WERE USED BY ANCIENT PEOPLE BUT TRADITION DIFFERED IN DIFFERENT LOCATIONS AND CULTURES. 5). HELIACAL RISING OF CERTAIN KEY STARS (SIRIUS/SOTHIS, PLEIADES)
IN THE TROPICS THE SUN CAN GO DIRECTLY OVERHEAD BUT IN THE ARCTIC AN EVEN NEATER THING CAN HAPPEN THE MIDNIGHT SUN. MULTIPLE EXPOSURE BELOW IS TAKEN ABOVE THE ARCTIC CIRCLE (LATITUDE > 90-23½) NATIVES OF NORTHERN CANADA START THEIR YEAR WHEN SUN FIRST BREAKS THE HORIZON.
ABOVE THE ARCTIC CIRCLE THE SUN CAN STAY ABOVE THE HORIZON CONTINUOUSLY (24 HOURS PER DAY) LOWEST POINT OF SUN IN PHOTO IS MIDNIGHT (HIGHEST POINT in opposite direction)
METHODS FOR SETTING A SOLAR CALENDAR 1) SHADOW OF A GNOMON (VERTICAL STICK) or PINHOLE IMAGE OF THE SUN ALONG A MERIDIAN LINE {EGYPTIAN, CHINESE, EUROPEAN} 2) RISING OR SETTING POINTS OF THE SUN ALONG THE HORIZON {HOPI, EGYPTIAN, CELTS, etc etc} 3). ZENITH PASSAGE DAYS = THE TWO DAYS PER YEAR THAT THE SUN GOES EXACTLY THROUGH THE ZENITH IN THE TROPICS (-23.5 O TO + 23.5 O ) 4). DAY THE SUN FIRST BREAKS THE HORIZON IN THE FAR NORTH We ll take these one-by-one. ALL WERE USED BY ANCIENT PEOPLE BUT TRADITION DIFFERED IN DIFFERENT LOCATIONS AND CULTURES. 5). HELIACAL RISING OF CERTAIN KEY STARS (SIRIUS/SOTHIS, PLEIADES)
TARAJUNGO IN MALI MATARIKI IN POLYNESIA PLEIADES IN JAPAN THEY ARE SUBARU TO THE LAKOTA INDIANS : WINCHIALA SAKOWIN TO THE INCA THESE STARS ARE CALLED COLCA WHEN YOU NOTICE THE PLEIADES RISING, START YOUR REAPING, AND ON YOUR SOWING WHEN THEY ARE SETTING. THEY ARE HIDDEN FROM YOUR VIEW FOR A PERIOD OF FORTY FULL DAYS, BOTH NIGHT AND DAY, BUT THEN ONCE AGAIN AS THE YEAR MOVES AROUND, THEY REAPPEAR AT THE TIME FOR YOU TO BE SHARPENING YOUR SICKLE. HESIOD OF GREECE, 9 th CENTURY, BCE