astronomy test 2

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(98)Describe how gnomons keep time on a sunny day. When is the shadow cast by a gnomon the shortest, and how does the length of the shortest shadow vary over the course of a year (think about how the maximum altitude of the Sun changes during the year on our horizon diagrams)?

• Gnomons keep time on a sunny day by casting a shadow on the other side of a given wall, measuring the time of day • The shadow cast by a gnomon is the shortest on the summer solstice, when the sun is at it's highest point in the year • As the year goes on, that shadow gets bigger, up to the winter solstice, when the shadow is the greatest at a given time of day

49. Which celestial objects are associated with each day of the week?

• Sunday = the Sun's day • Monday = the Moon's day • Tuesday =; Dies Martis = the day of Mars • Wednesday =; Dies Mercurii = the day of Mercury • Thursday =; Dies Iovii = the day of Jupiter • Friday =; Dies Veneris = the day of Venus • Saturday = Saturn's Day

(73)There are two shafts within the Great Pyramid that appear to be astronomically aligned. Explain why it makes sense for one shaft to point toward Orion's Belt and the other to point toward the meridian crossing of Thuban. (HW)

• The southern shaft pointed toward Orion, was among the decans and marks hours of the night throughout the Egyptian Year • The northern path pointed toward Thuban which was the north star of the old kingdom. Egyptians said that it was circumpolar these star had the ability to circuit forever without setting. The northern shaft pointed towards Thuban, a circumpolar star at the time that was an "imperishable star" because it never set. It was believed the Pharaoh would ascend to this star to become eternal himself. The southern shaft pointed towards Orion's belt which stood for Osiris who symbolized birth, death, and resurrection. By pointing to Osiris the pharaoh was believed to be reborn.

93. Describe the evidence that the buildings in Chaco Canyon are positioned and constructed in a way to mark the extremes of the lunar cycle.

It has 9 and ½ turns and the moon's shadow lands on turn of the spiral that lines up in succession with the years.

57. Explain why a culture might recognize an alignment with the rising point of a particular bright star (hint: the Egyptians did this with Sirius) out of all the possible bright stars in the sky.

A culture might recognize a bright star because it corresponds with certain events, like Sirius coinciding with the Nile. Also, other mythological factors might influence whether a civilization takes specific interest in one bright star over another. Some might signify the new year for example.

54. Name and explain two major cultural functions of Astronomy in ancient civilizations.

Ability to establish an accurate and consistent calendar: A common calendar holds civilizations together by giving people something in common. A common calendar allows groups of people to partake in the same activities such as festivals and going to the market on the same days. Establish a Divine Mandate: In ancient times, royalty would predict events in the sky in order to prove that the Gods had selected them to be the rulers and that they were divine. A good calendar helped to make accurate projections in the sky.

81. Both Stonehenge and the Temple of Kukulcan appear to point at major solar rising points in the horizon (solstice or equinox). Describe the evidence that confirms Stonehenge is likely an intentional alignment and the evidence that the Temple of Kukulcan may not be intentional.

Because the stonehenge design is repeated over and over again at different sites. Kukulkan is not repeated anywhere else and it is not repeated. For all we know this may be a lack of design. There is no clear evidence.

(69)Without any complex tools, Anthony Aveni and his students describe how to construct a right angle using a circle. Explain how this works with a simple diagram.

Connect any point on the circle to the top and bottom of the diameter in the circle.

80. Explain two reasons why it is not likely that a culture would intentionally align a structure with an extreme rise/set point of Venus or any other bright planet.

First, it is extremely difficult to track such weird patterns in the sky. Second, whether its at its northern or southern most point in the sky, it really does not affect the earth.

46. Use a side view of the Moon's orbit and the Ecliptic plane to help explain why the Moon doesn't undergo a lunar or solar eclipse every month.

New moon/full moon diagram with 5 degree angle. The shadows miss each other

52. Explain the significance of the Star of Bethlehem story in the gospel of Matthew by summarizing how this story shared ideas and traditions seen in other cultures in Egypt and Mesoamerica.

. In the Gospel of Matthew, the Star of Bethlehem drew the wise men from the east to Bethlehem to see Jesus's birth. The appearance of celestial objects in the Mayan and Egyptian cultures signified royalty, and significant human events. For example, Mayan rulers incorporated celestial symbols into the badges of officers and as signs of authority. Also, the Egyptian king's public appearance on the throne was equated with the sun's arrival on the horizon.

(74)What is the significance of the 70 day time period to the Egyptians. Why, for example, did the purification of a dead body (mummification) take 70 days? (HW)

.• The 70 day period is important because it was the 70 days it took for the journey of the Decans in the Underworld • In addition, Siruis for a 70 day period disappears from the night time sky. During this time they were up in the daytime. The Egyptians called the stars departure a death The 70-day period was both to describe the movement of the deacons and of Sirius in the sky. The deacons imitated Sirius in that they disappeared and reappeared 70 days later in the sky. During this time they were up with the sun, thus invisible. The Egyptians saw this disappearance as the deacon's death. The deceased where thought to be a stars, so mummification took 70 days to mimic the death and rebirth of the deacons. At the end of the 70 days, the dead were reborn

94. Describe two lines of evidence that indicate the north road was constructed not so much for practical use but instead for ceremonial use.

A lot of buildings with potential alignment. Odds are some of the are pointed by random; some solstice and some extreme. The land is clear and very straight because there is no major settlement past the road. There is simply no destination.

-43. Explain the difference between a solar eclipse and a lunar eclipse. Why are solar eclipses less common than lunar eclipses?

A solar eclipse is when the moon is between the Sun and Earth, causing the shadow of the moon to fall on a specific location of the Earth. A lunar Eclipse occurs when Earth is between the moon and Sun and the shadow of the Earth falls on the moon. Solar eclipses are less common because the earth's shadow is much larger than the moon and is thus more likely to be cast.

88.In the discussion of the Temple of Hathor at Dendera, Sir Norman Lockyer had proposed that the temple is aligned with a star in Ursa Major or Draco. What is wrong with this idea? According to texts found at the temple, what was observed from the rooftop and why did this observation coincide with the Egyptian New Year? (HW)

According to Lockyer's calculations the alignments would only work if the temple was 3,000 to 4,000 years older. The text describes the observing of the heliacal rising of Sirius, which is considered the mother of New Year.

(67)Describe the phenomenon that occurs at the Temple of Kukulcan on one of the two equinox days each year at sunset.

As the sun would slowly set, the snake, caused by light and shadows, would slither up and up the temple staircases when the sun sets due west.

78. Why must alignments with bright star rise/set points be very precise in order to be plausible?

Because there are so many stars that are located extremely close to the star in particular they are studying. There were too many close stars to be absolutely certain. If you are ½ a degree off, then you will be inaccurate.

90. Describe the orientation of Pueblo Bonito and how it is related to the seasonal motion of the sun.

By the midpoint sun in day, or sunset/sunrise in equinox: Gliff on Fajata has the same shape as pueblo bonito and the spiral gliff with the dagger. The shape of Pueblo Bonito is similar to the shape of the horizon with the meridian diagram.

62. The more complex and accurate a calendar is, the more advanced is the culture that constructed that calendar." Explain the logical flaw in this statement.

Calendars advance in diverse ways according to local traditions and needs, so they cannot be used as yardsticks of cultural achievement. Different calendars have different purposes.

87.Structure J at the Zapotec temple of Monte Alban in Central America has an alignment that seems to point toward a particular place on the horizon where the bright star Capella can be seen. Explain the significance of Capella and the what was likely observed here and at the neighboring building, Structure P. (HW)

Capella made its first reappearance in the predawn sky on the first of the year's two zenith passages of the sun.Within structure P is a tube that points straight to the zenith, and it, along with Structure J's front stairway, point to Capella. This shaft, the behavior of Capella, and the stairway orientation of structure J permit the light from the zenith sun to enter a chamber.

59. Explain what ethnocentrism is and briefly describe an example where this approach has been used in the field of archaeoastronomy and why this approach is flawed.

Ethnocentrism is, essentially, measuring the achievements of other past societies against our own, using ours as a yardstick. It is putting our culture on a pedestal. Ex: In Ethiopia, a man determined the days between planting and harvesting by tying a knot in a cord worn around the ankle for each day. People were not impressed with his conclusions because it was irrelevant to their lives. The flaw can be that we attempt to make what we observe about their society conform to ours.

89.What are two lines of evidence that no one lived in the large multi-room buildings constructed by the residents of Chaco Canyon?

First, there is no air circulation, and no ventilation. Second, It was so dark there is no light. It is more likely to be considered as a ceremonial destination.

(66)According to Anthony Aveni, the civilization that built Chichen Itza lasted until about the 9th century AD. Aveni says there had been an advanced, progressive civilization in that part of the world for at least how many years in total? What are two pieces of evidence of their advanced nature?

For about three thousand years. They had (1)specific and accurate calendars along with an established (2) written language that they used often.

65. What is a hierophany? Briefly describe two examples of hierophanies in Archaeoastronomy.

Hierophanies are locations where the appearance of a certain celestial object creates a visual effect through sunlight and shadow. The tomb at Newgrange is an example, when the winter solstice illuminates the glyphs and corridor at the back. Another is the pyramid of Kukulcan, where the body of a serpent is cast on the stairs during the equinox afternoon.

84.Explain the structure of kivas of the Pueblo and Anasazi indians in the American southwest. Specifically, why were they built underground and entered via climbing down a ladder through a hole in the ceiling? Why did they use four large wooden poles for roof supports, as opposed to some other number? Why were they round, as opposed to some other shape? (HW)

Kivas were circular and covered by a roof and one entered through a hole in the ceiling and a wooden ladder provided access to the floor. They were built underground because the indians believed their ancestors came from the underworld. They would go through a whole and climb down a ladder because it is symbolic component of the chamber going into the underworld. The four posts represent the four trees in the underworld. The Kiva is round because the world's rim is round.

92.Define the minimum and maximum extremes of the Moon. How long is the cycle of lunar rising points along the horizon? What evidence indicates this cycle was tracked on Fajada Butte?

Maximum: Outer edge of the spiral Minimum: in center extremes of the spiral gliff. They observed its long cycle on the center of the spiral.

60. Briefly explain two potential problems with using first-hand accounts to understand the ancient practices of a particular society

One problem is that some information is sacred and therefore withheld, possibly leaving out important details that could change the meaning. Also, the ethnographer could influence the worldview and then a later investigator may think that it was firsthand knowledge.

48. Two of the most easily recognizable constellations that are up in the sky at this time of year are Leo and Orion

See Paper

(100)What is the analemma? Use a horizon diagram to help explain what causes the north-south motion of the Sun along the meridian over the course of a year.

Solar Analemma. A Solar Analemma is a graph or plot that shows the position of the Sun in the sky at a single location and at the same time of the day throughout a year. ... This is called the Sun's Analemma curve

83. Describe the sun dagger phenomenon in Chaco Canyon in the southwestern United States. Draw a diagram of the different light and shadow patterns seen on the solstices and equinoxes. A video that shows this is http://accad.osu.edu/~aprice/works/sundagger/index.html.

Summer Solstice: The dagger is piercing through the center of the spiral Winter Solstice: There are two spirals cutting through the left and right sides of the spirals. Fall and Spring Equinox: Spiral pierces just to the right of the center. There is also another dagger piercing the middle of the tiny spiral. This would be the pecked out spiral for the dagger to show the winter solstices. We see this all over the southwest with rock art gliffs.

53. Explain the origin of the Christmas holiday. Why do we celebrate Christmas in December 25 instead of in April, the time of year most scholars believe Christ was born?

The Christmas holiday originated from Mirthraism, an early competitor of Christianity. Mithra was an avatar of the sun, in charge of order, judgment, and preservation. His birthday was December 25, which coincided with older calendars as the winter solstice. We celebrate Christmas on Dec. 25 instead of in April because the early Christians chose the birth of Christ as this date to successfully integrate long-standing poplar traditions with the imagery of a new religion.

51. In most cultures, the gods associated with the sky, weather, rain and lightning are male, but the Egyptians personified the sky as a goddess. Explain this difference (why the Egyptians don't also use a male god to associate with the sky)

The Egyptian sky god, Nut, was female because in Egypt it rarely rained. The main source of water (life-giving fertilization) was the Nile, not the sky. Therefore the river God was a male known as Osiris.

82. Regarding the tomb in Ireland known as Newgrange. Explain how this is aligned and why that alignment makes sense culturally, then explain what other evidence supports the assertion that this alignment was intentional.

The Irish Tomb with light flooding in the Winter solstice. It is associated with death and rebirth of the sun. Also there are gliffs all over the wall representing death and rebirth.

50. What was the main divine role of the Sun in the cultures described in the reading? What was the main divine role of the Moon in these cultures?

The ancient cultures saw the Sun as the source of all authority, law, and social order. Re, the Egyptian sun god, ordered the world. Shamash, the Babylon sun god, was judgment and justice. Varuna, in Vedic India, guarded cosmic law and order. The main divine role of the moon was timekeeping. Khonsu, to the Egyptians, was the moon (the "runner") and the basis of calendars; as well as Thoth, the regulator of time and seasons. Sin, for the Babylonians, was the "lord of knowledge", and presided over the calendar and astrological divination. The Inca's thought the moon the sun's wife and calendar-keeper.

85.Explain why the Pawnee earth lodges had four poles with specific colors. In other words, what do those colors seem to correspond to? How is the constellation Corona Borealis related to the Pawnee lodges and sky lore? (HW)

The four colors represent the special status of the four pillars of heaven. They were the four world quarter stars that top represented hands to heaven and the bottom represented the feet into the ground. The constellation was associated with the smoke hole and the zenith

(75)The tombs of Chinese royalty are usually oriented north-south. Explain why the Emperors usually oriented their tombs and palaces so they had to be approached form the South. In other words, why did these leaders associate themselves with the North? (HW)

The heavens revolved around the "Apex of Heaven", or the North Pole. The heavens revolved around the apex, and the world around the emperor. He provided stability and order to the world, the steady spot at the center like the apex. That is why the tombs are oriented north south, so that when approached, it is like moving north to the center of the world, where stability originated.

(97)What is the definition of "the meridian"?

The meridian is the great circle of the celestial sphere that passesthrough its poles and the observer's zenith. We can use it as a time keeping device when things cross the meridian (Sun at highest point in sky = shortest shadow.

45. Why does the Moon turn a deep red color during a lunar eclipse?

The moon turns red due to an effect known as scattering. Scattering occurs because light from the sun has to filter through the atmosphere and when it does the atmosphere tends to filter out the blue and only red passes through.

(70)According to Aveni, what is the significance of the number 13 in Mayan culture? The calendar round is the amount of time it takes for the 260-day (sacred round) tzolkin and the 365-day (agricultural) haab calendar to synch up again after starting together on day one. How long is a calendar round, and what supposedly occurred at the end of this cycle?

The number 13 is significant because it represent the 13 layers of heaven. The calendar round takes 52 years and the people was anxiously await for the star Pleiades to pass through the sky again at the end of this cycle to signify that the people did enough to satisfy the gods.

(68)What does the planet Venus represent to the Maya?

The planet Venus represents the Sun's Twin/ God of War. They also believed it controlled the weather.

64. Some astronomers attempt to reconstruct sightlines that connect buildings to points on the horizon, such as prominent notches silhouetted in a distant mountain range. Explain the potential problem of this approach, why it may lead to incorrect conclusions.

The problem lies in identifying the meaningful alignments. For example, Mursi sun watchers stood by a favorite tree or boulder to make observations instead of building a more permanent marker. Many dates in the Hopi solar calendar are marked by tiny notches. There is generally no obvious natural feature in the direction of the solstices, making locating these difficult.

63. Explain why solstices were observed by more cultures while equinoxes were rarely observed.

The solstices were observed more because they are tangible. The sun reaches the physical extremes of its motions along the horizon. It defines a natural division of the earths orbit. The equinoxes would have only have been observable as a halfway point between the solstices and are not as significant to ancient cultures. Equinoxes didn't help track time like solstices did.

(95)What evidence exists outside of the Chaco Canyon area that indicates the solstice alignment found at the sun dagger is likely intentional? Explain.

The spiral with the dagger piercing is far to specific and carefully placed for it to be unintentional. The daggers appear in such a position that had to be on purpose. This could have been to keep track of harvest or celebrations. In addition, repetition, similar gliffs at significant times of the year.

91.Describe the evidence on Fajada Butte that indicates the orientation of Pueblo Bonito is intentional.

The sun dagger spiral seasons when observing the sun. The gliff that appears looks exactly like the orientation of Pueblo Bonito.

(71)The Venus cycle, the time it takes for the motions of Venus on the horizon to repeat, takes how many years? Briefly describe a couple of reasons why the Maya studied Venus so closely.

This takes about 8 years. This is because they believed Venus to be the God of War. They were affected by the wrath they believed the planet contained. They also believed that the planet had a large control of the weather.

86.Explain how the Sun "weaves" the threads that make up the floor of the Kogi temples. (HW)

Throughout the year as the sun moves north and south then back north, it "spirals" around the world's spindle. It "weaves" the thread of life into an orderly fabric of existence and the cyclical changes of the sun's daily path are transformed to a cloth of light on the temple floor.

44. Explain the difference between an annular and a total solar eclipse. Why are solar eclipses sometimes annular and sometimes total?

Total: The moon is closer to the earth and appears larger in the sky, as such the moon covers the entire sun . Annular: The moon is further from the earth and does not completely cover the sun. The eclipses vary because the moons orbit is an ecliptic, meaning that at different points of the year the moon can be closer or further away from earth.

58. Even though observations of the sky were likely no more important than the surrounding landscape for ancient cultures, we feel that we can potentially learn more by studying how people observed the sky and how it influenced them. Explain why.

Unlike landscapes we are able to view the sky directly; landscapes are ever changing and were likely very different for ancient cultures. Also through our modern technology we are able to reconstruct mathematically exactly what our ancestors were viewing in the sky at a particular location and time.

79. Briefly explain two reasons why an archaeological alignment with an extreme rising or setting point of Venus may be considered significant. What supporting evidence indicates Mayan alignments with Venus (for example at the Caracol) are likely intentional.

Venus is bright and easy to track so this is believable. It also does repeat its cycle every 8 years. If you are careful and cautious, it is recognizable. The Caracol is intentionally oriented to view Venus because its orientation is extremely precise, this coupled with all of the folklore of the culture venerating Venus leads us to believe that is built in alignment with the planet. The degrees of its foundation are purposely oriented around Venus, as nothing as mentioned in the folklore is apparent in the general direction of the Caracol.

61. Not all apparent astronomical alignments are real and/or intentional. After all, everything has to point *somewhere*. Explain two ways we can distinguish between accidental and intentional astronomical alignments by describing the two examples (from Scotland and Central America) from the reading.

We can distinguish by either seeking statistical confirmation (identifying a group of several monuments in which a certain type of astronomical alignment occurs repeatedly, such as the recumbent stone circles of Scotland that have a consistent orientation relating to the moon), or by finding corroborating archaeological evidence of different forms (such as with pre-Columbian Mesoamerican where we found accounts, iconography, and written records for Venus).

(72)Read http://bit.ly/1QoNiYv about the zodiacal light and answer: What causes the zodiacal light (what is the source of the light)? Why does the light appear in a band along the zodiacal constellations? Why is zodiacal light best seen during the Spring from the northern hemisphere? (HW)

What causes the light?- Sunlight reflecting off dust gains that circle the sun in the inner solar system. Why does the light appear in a band along the zodiacal constellations?- It appears as a band because these grains of dust are densest around the sun and the dust gains lie in the flat sheet of space around the sun Why is zodiacal light best seen during the spring from the northern hemisphere?- The light is best seen during the spring from the northern hemisphere because the ecliptic stands nearly straight up in autumn with respect to the western horizon. It can be seen for up to an hour after dawn.

47. Explain why "eclipse seasons" occur about every six months. As part of your answer, define what a "node" is with respect to the Moon's orbit and how the line of nodes determines whether eclipses occur.

When nodes point toward the sun, its possible for an eclipse but that only happens about six months. There cannot be an eclipse when the nodes are not facing the sun and they aren't always facing the sun.

(77)Though no written records exist, name and briefly explain two pieces of evidence (many are described) that support the idea that the tomb at the Irish tomb of Newgrange was astronomically aligned purposefully (rather than accidentally). (HW)

With its main axis nearly aligned with the direction of the winter solstice sunrise, even the geometry of the entire structure emphasizes the astronomical orientation. In addition, details like the "roof-box", the quarts, and the vertical "axis-line" carved down the middle of the entrance stone confirm its intent.

56. Is an alignment with summer or winter solstice sunrise more significant than an alignment with the most extreme northern or southern moonrise? Explain why or why not.

Yes, Lunar extremes occur roughly every 18 years and because they are so rare have little practical value in measuring time. Solstices occur roughly every 6 months and help to measure agricultural seasons and helped civilizations plan the planting and harvesting of their crops.

55. Is an alignment with summer or winter solstice sunrise more significant than an alignment with the equinox? Explain why or why not.

Yes, an alignment with a summer and winter solstice is more significant than an alignment with an equinox because solstices were a more practical measurement than equinoxes. For example, Solstices helped measure agricultural seasons and let civilizations know when it was time to plant or harvest their crops.

(99)Explain why it is easier to time an object's meridian crossing ("transit") as opposed to the object's rising or setting times (three reasons).

You do not have to worry about any obstructions on the horizon The rising time of the sun is varies from day to day The bend of lightbeams in the atmosphere has less of an impact when looking for an object to cross through a north-south line compared to rising above the horizon.


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