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Questions from the first part of the class, to be covered on Exam #1.

(1)

Two of the most easily recognizable constellations that are up in the sky at this time of year are Pegasus and Ursa Minor. For each of these two constellations, find the following information:

• Approximate location in the night sky for this time of year, based on the star chart for early evenings in January (see skymaps.com for a simple downloadable PDF chart for January). That means I want an approximate altitude (in degrees) and azimuth (direction of the nearest horizon point for the constellation),
• star chart (sketch of the pattern of the 6-9 brightest stars and connecting lines that make up the constellation),
• name of the two stars designated alpha and beta (usually the two brightest),
• 2-3 sentence summary of the mythology behind the constellation.

The rest of this information pretty easy to find on the web. A good place to go for mythology is http://www.comfychair.org/~cmbell/myth/myth.html, but remember to keep your summary fairly short so it is easy to remember the most important parts. A good place to go for myths and interesting objects in the constellation is http://www.dibonsmith.com/constel.htm. For star names and other information, try http://www.astro.wisc.edu/~dolan/constellations/. To find the approximate altitude and azimuth (azimuth means direction along the horizon, like northeast, south, west, etc), you should use the star chart as indicated, but you may also consult the Starry Night software that is installed on the computers in the Astronomy lab, which you can use if you finish early in lab ***OR*** go outside and *FIND* them with your own two eyes on a clear night (all are easily visible this time of year). When you are done, go out at night and find the constellation and explain what you know to a friend or classmate. It's fun to do and easier to remember that way. (HW)

(2)

From the reading "Cargo Cult Science", explain "why the planes don't land" to a typical islander who might ask, in a few sentences. (HW)

(3)

From the reading "Cargo Cult Science", briefly summarize the story of Mr. Young's experiment and why those who ignore his work cannot really trust their conclusions. (HW)

(4)

From the reading "Cargo Cult Science", briefly explain the story of the Millikan oil drop experiment and the subsequent history. Explain why this was such an embarrassing episode for scientists. (HW)

(5)

According to Feynman in the reading "Cargo Cult Science", what sort of actions should scientists take in order to have the utmost integrity and therefore confidence in the accuracy of the results? Briefly explain two examples. (HW)

(6)

A common misconception about the seaons is that warmer summers are caused by Earth's elliptical orbit, that the Earth is warmer in June, July and August because it is closer to the Sun. Summarize two basic arguments that contradict this idea.

(7)

Another common misconception about the seasons is that warmer summers are caused by the tilt of the Earth because that tilt means the Northern hemisphere is closer to the Sun during summer than the Southern hemisphere. Summarize the argument that refutes this idea.

(8)

Be able to draw a celestial sphere and identify the locations of the Celestial Equator and the two celestial poles.

(9)

Describe the daily motion of stars. Be able to draw and explain how the daily motion of stars looks from different latitudes on the Earth (such as the equator, mid-latitudes and the poles).

(10)

What does solstice translate to literally, and why does this make sense? In other words, describe what is happening to the Sun's rising or setting point near the solstice. (HW)

(11)

What does equinox translate to literally, and why does this make sense? In other words, what is happening in the sky during the equinox? (HW)

(12)

What is the Milky Way as it appears on the sky? In other words, describe the Milky Way on the sky and explain what it is we are actually looking at when we see the Milky Way. (HW)

(13)

What is the Age of Aquarius, and what does it have to do with the Earth's precession? What exactly is precession (diagram would help)? (HW)

(14)

Where does the word "month" come from and why is a month about 30 days? (HW)

(15)

Why can't we use the repeating phases of the Moon to keep a calendar for use in, say, an agricultural calendar? (HW)

(16)

The death of Osiris is typically observed in Egyptian mythology on the 17th day of a certain month. Explain why that day is the appropriate time for such a ritual. (HW)

(17)

What is the definition of "heliacal rising"? Why was the heliacal rising of Sirius significant in the Egyptian calendar? (HW)

(18)

Explain why some stars are circumpolar. Use a celestial sphere diagram (something like figure 2.5c from section 2.1 of OpenStax Astronomy with labels and examples of circumpolar and non-circumpolar stars) to help explain why stars at higher declinations are more likely to be circumpolar stars. A diagram by itself is not sufficient to answer this question.

(19)

Explain why we see different constellations overhead at the same time of night on different days of the year. A simple diagram may help (for example, a simplified version of figure 2-6 from chapter 2.1 of your OpenStax Astronomy text, which I showed something similar in class).

(20)

Explain why longitude doesn't matter in terms of the stars we see at night. In other words, explain why we in Fort Worth see the same sky at a local time of 9pm as the residents of Baghdad, Iraq (at the same latitude but different longitude) see at 9pm local time in Baghdad.

The following 5 homework questions are from Chapter 2 of the book "Echoes of Ancient Skies", which can be found on d2l.tcu.edu.

(21)

What is the purpose of the "stretching of the cord" ceremony in ancient Egypt? What is it analogous to in today's society? (HW)

(22)

What is the Cahokia Sun Circle? What makes us think it is an astronomical (solar) observatory? What is an argument against this interpretation of the circle? (HW)

(23)

List three examples of potential errors that make it virtually impossible for ancient skywatchers to pinpoint the exact location of the moonrise or moonset on the distant horizon on a daily basis. (HW)

(24)

What is the Caracol of Chichen Itza, and why did 19th century explorers suppose that it was an astronomical observatory? What are two pieces of evidence the book's author uses to argue the Caracol may have been an observatory? (HW)

(25)

Describe the purpose of the sky measuring station at Yang-Chheng, and briefly explain how it works. Why was it appropriate that this astronomical observatory be stationed at this location? (HW)

(26)

From the reading "Philosophy and the Scientific Method," what is the primary difference between a scientific and a non-scientific belief? What is the major weakness of using irrefutable beliefs as a basis for a system of knowledge? I strongly recommend you check your answer on this one with me. (HW)

(27)

In the reading, Pine says that in order to distinguish correlation from causation, we have to isolate variables to see if one effect really causes another or if perhaps the cause is some other unknown, unanticipated thing. In the context of the sex education study, describe the error made by the angry letter-writer. (HW)

(28)

Use the barrel of apples example from the reading to help explain why a small representative sample is better than a large unrepresentative sample. Give an example of a representative and unrepresentative sample of apples from the barrel as part of your answer. (HW)

(29)

What is the ecliptic? Be able to draw the difference between the Sun's daily and annual path on a celestial sphere diagram (see figures A2 and A4 in the "Stellar and Solar Motions" file on D2L for reference).

(30)

Describe what is happening to the Sun as it moves about the Celestial Sphere on (a) the Vernal Equinox, (b) the Summer Solstice, (c) the Autumnal Equinox and (d) the Winter Solstice.

(31)

What is a sidereal day? How and why does it differ from a solar day? Use a diagram to help explain this answer (see figures B1 and B2 in the "Stellar and Solar Motions" file on D2L for reference).

(32)

Be able to draw a simple horizon diagram (horizon plus hemispherical sky) from Fort Worth's latitude, showing the altitude above the horizon of the NCP, Celestial Equator and June/December paths of the Sun. Be able to use this diagram to explain two reasons why summer months (June) are warmer in Fort Worth compared to winter months (December).

(33)

What is special about the latitudes of the Tropic of Cancer (23.5 North) and the Tropic of Capricorn (23.5 South)? Be able to draw a horizon diagram from these specific latitudes to help explain what makes them significant.

(34)

What is special about the latitudes of the Arctic Circle (66.5 North) and the Antarctic Circle (66.5 South)? Be able to draw a horizon diagram from these specific latitudes to help explain what makes them significant.

(35)

Use a horizon diagram to help explain why the polar regions with a high northern latitude are always cold, even during the summer. Also use the diagram to help explain why the variation in day length is so extreme compared to our latitude.

(36)

Use a horizon diagram to help explain why the tropical regions (between the Tropic of Cancer and the Tropic of Capricorn) don't have dramatic seasonal changes like our latitude.

(37)

Use a horizon diagram to help explain why southern latitudes experiences seasonal changes (changes in day length and maximum altitude of the Sun) that are opposite to those we experience in the northern hemisphere.

(38)

Consider the possibility that the Earth's axis is not "tilted 23.5 degrees from the perpendicular" but instead is EXACTLY perpendicular to its orbital plane. On a Celestial Sphere, show how this changes the location of the Ecliptic. Draw and label and Ecliptic and the Celestial Equator in this case.

(39)

If the Earth's axis were perpendicular to its orbit, how would that change our seasonal diagram for TCU? For this case, draw and label on a horizon diagram the NCP, Celestial Equator, June path and December path of the Sun. Use this diagram to explain why in this case we would not experience seasonal differences at TCU.