Earth Space Standards – History
I) I have a few key standards that I believe are omitted by the committee, and yet essential to all students of Earth Space Science
B) A teacher of earth and space science must demonstrate a historical understanding of earth and space science, and in this effort, I refer to the importance of Astronomy throughout history. The teacher must:
There is no branch of science that has had as significant an impact on world history and culture as Astronomy. From the dawn of human civilization when man first took a good look at the night sky, it has proven to be mysterious, awesome, fearsome, and difficult to unravel its secrets. Due to the study of Astronomy, the calendar was created, myths written, leaders made fearful of leaving their houses, presidents altered their schedules, world explorers exploited the conquered, and institutions challenged. The courage of just one man, Nicholas Copernicus, changed forever man’s view of himself as well as the way western civilization looked upon a Judeo-Christian God. It was the heliocentric model that changed man’s look on the Universe, man’s look on this Earth, and man’s look on himself. It opened the Age of Enlightenment and brought a close to the Dark Ages.
1) Understand and be able to explain to students the origin of the calendar and its importance to civilization.
This unit is divided up into three parts, each of which builds upon the others. The first section is about what the earliest people saw when they looked at the night sky. The study of the stars gave rise to the calendar and the prediction of when to plant crops to insure a successful harvest, the ability to navigate by Polaris and thus venture out from a city to unknown lands with the tools to safely return, and the use of the planets among the constellations as predictors for various activities from war to celebrations.
Archaeoastronomy
Ever since man took a good look at the night sky, he has wondered why things move and look as they do. Astronomy is the oldest of all sciences and its history is really very interesting. While the ancients did not make a lot of early attempts to solve the riddles of celestial motion, they certainly worked to decipher those motions for basic survival needs. Some of the earliest drawings found in the prehistoric caves of France depict lunar cycles, as do ivory sculptures from Africa ... both over 20,000 years ago. The ancients had nothing to do in their evenings for entertainment. They lacked a big screen tv, ice cream desserts, night club dancing, or even something as simple as a soft light and engrossing book. With so little to do, as well as no city light pollution, stargazing for wonderment was replaced with stargazing for understanding. Basic questions had to be answered. Our story of the most ancient historical Astronomy begins with the Babylonians.
An early chapter of the Biblical book "Genesis" describes a man named "Nimrod." While his name may carry negative meaning today, Nimrod was described as a mighty hunter and credited with the founding of the cities of Babylon and Ninevah. As the potential founder of one of the greatest kingdoms ever, it becomes exciting to think about how such a mighty man may have built such great cities. Certainly his skills as a hunter may have been unparalleled, but was there more to this man than mere brute strength like Conan the Barbarian? Could Nimrod have also been blessed with a high level of intellectual and intuitive ability?
What sort of observational understanding must Nimrod have possessed which would bring about a change for a nomadic people toward a more settled civilian form? Did Nimrod and his assistants figure out something from watching the stars which might give them such a competitive advantage over the other surrounding tribes and lead to the development of a mighty kingdom? Below is my thinking on this subject.
The ancient Babylonians mapped the path of the sun against the stars of the night sky. As the sun moved through the sky, it moved through a path called the ECLIPTIC. Although the light of the sun makes impossible the seeing of the sun and stars simultaneously, the ancients knew that the stars were still there, but just blinded out of sight. Through careful recording of the changing positions of specific star constellations throughout the year, early astronomers were able to trace the sun's path through such star groupings. The 12 constellations through which the sun traveled in the ecliptic became known as the ZODIAC.
Below are some key terms:
ECLIPTIC = the apparent circular path of the sun across the sky.
ZODIAC = twelve constellations which fall in the ecliptic (ZONE OF ANIMALS)
The image on the previous page shows the star groupings which occupy the ecliptic.
The Zodiac = CAPRICORN, AQUARIUS, PISCES, AIRES, TAURUS, GEMINI, CANCER, LEO, VIRGO, LIBRA, SCORPIO, and SAGITTARIUS, starting in June and finishing in May. A thirteenth constellation occupies the ecliptic, Ophiuchus, between Libra and Sagittarius, but is not included in the Zodiac calendar.The ancients also noticed that certain aquatic constellations were occupied by the sun during the worst storm periods ( Capricorn = sea goat, Aquarius = water bearer, Pisces = fish), and this helped develop a predictable calendar with best dates for planting spring crops. The development of the calendar was the critical piece of information which enabled a civilized society to develop for the people could build a walled city for protection, farm food on soil in surrounding areas without a need for wandering and gathering, and predict the times for successful planting times. A person, like Nimrod, who could predict the best time for planting would give his followers a strong advantage.
As you can see in the diagram to the above, the earth is following its path around the sun, moving counterclockwise. While we know this today, the Babylonians thought the sky rotated. To their perspective, the constellations of the Zodiac changed on a monthly basis. In the image to the left, earth star watchers would see Leo straight to the south at midnight, while at noon the sun would be occupying a spot in the constellation Aquarius. Since Aquarius and Pisces are considered two of the three water constellations, the sun's position in them would indicate the impending rainy season and be a good time for crop planting. It was not so much a matter of which constellation was visible at night as it was which constellation was occupied by the sun.
The Babylonians went further following the development of their calendar, for they noticed that several starlike objects did not remain in close association with the stars of specific constellations. These 7 objects wandered in and out of the 12 zodiac constellations. The seven objects are Sun, Moon, Mercury, Venus, Mars, Jupiter, and Saturn ... the day and night lights as well as the 5 naked-eye visible planets. In fact, the word "planet" is derived from a Greek word for "wanderer." There was a belief that the location of these 7 objects among the various zodiac constellations held great meaning. Armies might be encouraged to wage war if Mars, the red planet, was in Sagittarius. An entire study developed called "Astrology" that offered to explain the meaning behind the location of such celestial objects. People believed that their life histories would be influenced by the birthday orientation of the 7 objects, and others would make decisions based on the same. Even today, a large percentage of the population regularly consults the newspaper for their daily horoscope and hopes to find money or romance by the end of the day. Nancy Reagan, wife of the late former American president Ronald, was a big believer in meaning attached to the zodiac and planet motions. Ronald's advisors had to consult with Nancy first about scheduling meetings lest his meeting occur on an ominously bad date. Calendars were given to the advisors from Nancy and her astrologer/advisor with dates blacked out for any activity for her husband. It seems strange now to look back at the 1980's when Ronald was president and think that our national policies may have been influenced by his wife's astrologer! The image below is a modern look at the Astrologer's chart with dates for each zodiac sign and thoughts about the meaning of planets and sun and moon. While I do not hold any belief in the motions of the solar system influencing my life, plenty of others do. The Astronomy Society of the Pacific holds annual meetings for astronomy educators, one of their stated missions being to debunk myths in Astronomy ... Astrology being one of them. However, if you still are interested in learning more about Astrology, click on the chart image, or go to a more detailed study at Astrology.
Development of the Calendar
The ancient Greeks are credited with organizing the first widely accepted calendar, dividing the week into seven days based on the motions of the seven planets. Since the Greek word "planet" means wandering object, the Sun and the Moon were considered planets as well. These seven "planets" were then organized by an order based on their stability in the sky. Saturn appeared to move the least against the background stars, so it was considered the most stable. Next in line was Jupiter, and then Mars. Surprisingly, for most astronomy students, the Sun was the next in line, in terms of its stability. It moved in the sky more than Mars, and yet actually appeared to move less wildly than either Venus or Mercury which came afterward in the Greek system. Finally, the least stable "planet" was the Moon, for it moved like the Sun, but went through cyclical phases.
Now, the Greeks divided the day into 24 hour time periods, and named each hour after the seven planets, ascending in time from the most stable planet to the least stable seven hours later, and then starting over again. This system looked like the chart below:
SATURDAY
/SUNDAY
/MONDAY
/TUESDAY
/WEDNESDAY
/THURSDAY
/FRIDAY
Saturn
/Sun
/Moon
/Mars
/Mercury
/Jupiter
/Venus
jupiter
/venus
/saturn
/sun
/moon
/mars
/mercury
mars
/mercury
/jupiter
/venus
/saturn
/sun
/moon
sun
/moon
/mars
/mercury
/jupiter
/venus
/saturn
venus
/saturn
/sun
/moon
/mars
/mercury
/jupiter
mercury
/jupiter
/venus
/saturn
/sun
/moon
/mars
moon
/mars
/mercury
/jupiter
/venus
/saturn
/sun
saturn
/sun
/moon
/mars
/mercury
/jupiter
/venus
jupiter
/venus
/saturn
/sun
/moon
/mars
/mercury
mars
/mercury
/jupiter
/venus
/saturn
/sun
/moon
sun
/moon
/mars
/mercury
/jupiter
/venus
/saturn
venus
/saturn
/sun
/moon
/mars
/mercury
/jupiter
mercury
/jupiter
/venus
/saturn
/sun
/moon
/mars
moon
/mars
/mercury
/jupiter
/venus
/saturn
/sun
saturn
/sun
/moon
/mars
/mercury
/jupiter
/venus
jupiter
/venus
/saturn
/sun
/moon
/mars
/mercury
mars
/mercury
/jupiter
/venus
/saturn
/sun
/moon
sun
/moon
/mars
/mercury
/jupiter
/venus
/saturn
venus
/saturn
/sun
/moon
/mars
/mercury
/jupiter
mercury
/jupiter
/venus
/saturn
/sun
/moon
/mars
moon
/mars
/mercury
/jupiter
/venus
/saturn
/sun
saturn
/sun
/moon
/mars
/mercury
/jupiter
/venus
jupiter
/venus
/saturn
/sun
/moon
/mars
/mercury
mars
/mercury
/jupiter
/venus
/saturn
/sun
/moon
The Greeks then gave the name of the day of the week after the name of the planet which fell on the first hour. Some of the names are different from the Greek system because we have adopted some of the Norweigian names. The first three days are Greek in origin: Saturn's day, Sun's day, and Moon's day. Tuesday is derived from a variation on Aries as the god of war. Finally, the Norse gods are found for Woden's Day, Thor's Day, and Frie's day.
The information within this page was learned while I was attending the spring meeting of the AAVSO and HEA in Kohala, Hawaii in the summer of 2002. The AAVSO is the Astronomical Association of Variable Star Observers, and the HEA is the High Energy Astrophysics symposium. Dr. Karen Meech gave an evening talk about archaeoastronomy, and this was one of her topics.
But the Babylonians were not the only group to develop the science of Astronomy, and tracking the motion of the Sun or Moon were not the only items of interest to the earliest civilizations. Early peoples also were interested in the timing of the rising and setting or particular stars or constellations. These motions are called "heliacal risings and settings."
Imagine there is a particular star you like a great deal, say Sirius. Remember that the Earth makes a complete rotation in roughly 23 hours and 56 minutes. Yet we measure the length of the day to be 24 hours between high noons. The extra 4 minutes of time required for the Sun to be at the highest point in the sky is due to the necessary 4 minutes of time for Earth to revolve in its orbit and realign with the Sun. Meanwhile, the stars were properly aligned relative to the Earth 4 minutes previously. This disparity in time means that any given star will rise 4 minutes earlier each night. You look for Sirius, but on one sunrise, it is exactly in line with the Sun and therefore hidden in its glare. The following morning, Sirius will rise 4 minutes ahead of the Sun, but it will still be hidden in the Sun's glare. Eventually, a morning will come when you can see Sirius ahead of the rising Sun. This morning you would mark as a special event for you ... the heliacal rising of Sirius. Well, many civilizations followed heliacal risings and settings of various stars or constellations. The rising of the Pleiades, Sirius, Capella, and others were all used by different ancient civilizations to mark seasonal or festival-worthy events. While the Papagao Indians used the Pleiades heliacal rising at sunrise to mark seasonal events, the ancient Hawaiians used the heliacal rising of the Pleiades at sunset to mark important events.