to the heavens for the origins of time
The Sun and Moon are
the two celestial timekeepers that can be observed to measure time,
dates and the seasons. The rising and setting of the Sun marks the
day and night. The waxing and waning of the Moon indicates the progression
of the months.
time and space
Ancient astronomers and
keepers of time divided the annual course of the Sun across the
12 Zodiac constellations into 12, 30 degree segments. In a year,
the Sun moves across the Zodiac to complete a 360 degree circuit.
The Sun takes about a month to move from one Zodiac constellation
to the next. A reason why a year is divided into 12 months. The
Moon takes 29.5 days to complete a cycle from Full Moon to the next.
Another reason why a month, on average, is 30 days,
cycle across the Zodiac
During a moon-cycle,
the Moon moves across the 12 zodiac constellations. The first astronomers
divided the monthly orbit of the Moon into 28 different sections
called 'lunar mansions'. Each 'mansion' is approximately one day
of the lunar cycle, or about 12.2 degrees of the Moon's 360 degree
circuit. This 28 division of the Moon cycle can be divided into
four phase periods of the Moon. How 7 days was determined to be
a week, correlates with the 7 day moon phase division of 28.
named after celestial bodies
The 7 days of the week
are named after the 7 prominent celestial bodies that are observed
in the sky. The Sun, the Moon and the 5 visible planets, Mercury,
Venus, Mars, Jupiter and Saturn, have days of the week named after
them. English names for the 7 days of the week originated from Roman
and Anglo-Saxon celestial gods. Sunday is named after the Sun. Monday
the Moon. Tuesday was named after the god of Mars, Tiw, by the Anglo-Saxons.
Mercury which is referred to by astrology as the planet of communication,
was associated with Woden, god of poetry. Thus Woden day became
Wednesday. The god of Jupiter was Thor, Thursday. Freya was the
god associated with Venus, so Friday. Saturday is named after Saturn.
inventors of time
The system by which we
measure time today was founded 4,000 years ago in Babylon. Timekeeping
was devised by identifying and measuring the movement of the Sun
and Moon across the Zodiac constellations. Ancient priests of astrology
and astronomy devised a 360 degree system that plots and times the
course of the Sun in a year. The coordinate system can be easily
divided by 60, 30 and 15. A minute has 60 seconds. An hour 60 minutes.
One day of 24 hours divided by 2 is 12.
Due to study at the ancient
university of astrology, scholars developed astronomy, the calendar
|Apkallus, a Babylonian god, revealed
time, astrology and astronomy to civilization.
Many religions have an
association with time and the sky.
The Gregorian Calendar
is the everyday calendar we use today. In 1582, Pope Gregorian XIII
abolished the inaccurate Julian Calendar which Europe had used since
the time of Julius Caesar. The Gregorian calendar is an accurate
time and date measuring system that keeps in sync with the annual
course of the Sun.
The Julian Calendar
had a slight discrepancy, which over centuries caused it to become
10 days out of alignment with the seasons
The astrology calendar
is over 2000 years old. Because it has never been updated, it is
out of sync with the sky and the everyday calendar. Discover
how the astrology calendar became inaccurate.
Scholars show Pope Gregory XIII a chart of the Sun against
the Zodiac to indicate the location of the Sun throughout a year.
24 hour time and distance
The period the Earth
takes to complete a rotation is 24 hours. Navigation (longitude)
and celestial coordinates (RA right ascension) use a 24 hour and
minute system to measure distance. Using degrees, instead of hours,
is also applicable.
By watching the Sun and
stars move across the sky, you actually watch the Earth rotate.
The stars move towards the west one minute in distance, every minute.
Or one degree every 4 minutes. In an hour, the Sun and stars move
The Sun and stars rise
in the east and set in the west because the Earth rotates eastwards.
sky moves due to the rotation of Earth
Earth rotation = 24 hours
(360 degrees / 24 hours RA)
RA 1 hour = RA 60 minutes
One hour time = Earth
rotation of 15 degrees, or one hour of RA, right ascension.
Four minutes time = Earth
rotation of 1 degree, or 4 minutes of RA, right ascension.
tilt causes the seasons
The seasons occur due
to the tilt of the Earth's axis of 23.5 degrees of arc to its orbital
plane. The direct exposure of the Sun's rays onto the Northern and
Southern hemispheres alternates as the Earth revolves during its
yearly orbit. So when summer occurs in Europe in June, the opposite
season of winter occurs in Australia. Winter time for Europe is
December, when Australia has long summer days.
More hours of sunlight
occur during summer as the Sun travels a high, longer path across
the sky. Shorter days occur in winter as the Sun travels a shorter
path closer to the horizon.
More direct sunlight
due to the angle of the Earth in summer. The angle of the hemisphere
having a winter season is less direct, so shorter daylight hours.
chart below indicates how people living in opposite hemispheres observe
the ecliptic path of the Sun move across different horizons. The chart
also indicates that the declination of the daytime ecliptic at noon,
is opposite to the midnight ecliptic path.
: North South
to the chart to compare the difference between the ecliptic
path across the sky at midday and midnight in the Northern and
Solstice : 12 AM 12 PM
At midnight, 12 AM, the
arc of the ecliptic is opposite to its midday, 12 PM course.
The path of the ecliptic
has a seasonal pattern. At midday in summer, the Sun travels a high
arc (high declination) across the sky. At midnight in summer, the
ecliptic path is low and close to the horizon. In winter, the passage
that the sun travels across the sky is low, close to the horizon.
In winter at midnight, the ecliptic path is high overhead, as it
would be during midday in summer.
course of the ecliptic across the sky
People living in the
Southern hemisphere observe the Sun to rise from the East and move
across the Northern horizon to set in the West. In the Northern
Hemisphere, the Sun moves across the Southern horizon to set in
the West. Traveler's who visit an unfamiliar hemisphere sometimes
confuse North and South, if they refer to the Sun to get their bearings.
to the charts on an Astroplot, the seasonal course of the ecliptic,
its rise and set bearing, can be plotted over a 24 hour period for
each month of the year. Refer to the Astroplot, using the
'Clock Process' to identify the location of the stars in the sky
for any time and date.
from Astroplot indicate the course of the ecliptic for the Southern
Hemisphere in December
ecliptic at 12 Noon, December
ecliptic at 12 Midnight, December