Altitude & Azimuth for AST1040

Statement of Purpose:  This activity will demonstrate my ability to properly submit an activity write up for this class, as well as my ability to properly locate and record the location of a given object in the sky.  This activity will also show that objects in the sky (in this instance, the moon) change location and appearance throughout a given time period as seen from a given point on earth.

Statement of Procedure:  This activity required that I step outside, locate the moon and estimate it’s altitude (horizon being 0°, zenith (point directly above head) being 90°) and azimuth (360° horizon according to true north – true north being 0°, south being  180°), and to record this data along with the time of the observation and the appearance of the moon at that time.  The next step of the activity was to incorporate the observed data into a complete activity write up in such a way as to explain the activity, complete with analysis of the data to complete a statement of conclusion, and demonstrate a proper activity write up simultaneously.

Data:

Date	Time	Location	Lunar Altitude	Lunar Azimuth	Appearance
9/2/2011	9:20 PM	Home, N Denver	15 deg	210 deg	first quarter, half full, slight lean to the right
9/5/2011	7:02 PM	Home, N Denver	40 deg	180 deg	waxing gibbous, slightly more than half full, straight vertical
9/8/2011	6:34 PM	Home, N Denver	15 deg	140 deg	waxing gibbous, more than half full, slight lean to the left
9/11/2011	9:16 PM	Home, N Denver	25 deg	125 deg	Full Moon

Statement of Conclusion:  Throughout a period of nine days, the moon changes location and appearance as seen from a given point on earth.  The most noticeable change is my first and last recordings.  Both observations were made around the same time in the evening, but the results were drastically different, both in location and appearance.  The data would probably show more incremental changes if the observations were made closer together.  If I were to observe the moon on an hourly basis, I believe my data would reflect the moon’s altitude and azimuth changing more subtly while the appearance would stay nearly the same.  If I were to observe the moon on a daily basis, I believe my data would reflect the moon’s altitude, azimuth and appearance changing.  The observations that I collected could be broken down into smaller increments to show the subtle but steady motion of the moon across the sky as seen from a given point on earth.

1)      After having done your observations, do you think you could repeat these observations exactly in two weeks?  Why or why not?

a.       I could repeat the observations; however, they wouldn’t be exactly the same.  The moon would not be in the same place nor would it appear the same.  As the moon revolves around the earth and the earth around the sun, the moon will appear in different phases and locations in the sky from a given point on earth.  For instance, my first and last observations were only one week apart and they vary drastically.  In two weeks from my last observation, the moon would not be visible because the sun’s glare would blot it out (new moon).

2)      Must these observations be done during the night-time?  Why or why not?

a.       The observations can be done during the day-time as long as the moon is not in its “new moon” phase.  For instance, the Full Moon rises at about sunset, a Waning Gibbous Moon sets at a few hours after sunrise, a Third Quarter Moon doesn’t even set until about noon.  The New Moon is in the sky during the day, however it cannot be seen because the sun’s light “washes it out”.  So, no, the observations do not be done during the night-time, they can also be done during the day, providing the moon is in the appropriate phase(s).

3)      How accurate do you think your observations are? (Just how you feel about it)

a.       I would guess my observations are accurate to within about 20°.  It is difficult to see the horizon from my point of observation, as it is obstructed from view by trees, houses, mountains, etc.  Also, my estimations of azimuth are based on another estimation of where I am in relation to “true north”.  I feel like the appearances are accurately observed.  Ideally, these observations should be made from a large flat, unobstructed viewpoint.

4)      Imagine that another student made the same observations at the same time as you, except from a location 10 miles away from you.  How do you think that would affect the observations?  In other words, how different do you think they would be from yours?

If another student made observations at the same time(s) that I did, the results would be different, but not by much.  The appearance of the moon would stay the same; however the altitude and azimuth might be subtly different, maybe one or two degrees difference.  Also, the observations would depend on how similarly the other student and I estimate.