Moon Observation

LUNAR OBSERVING PROJECT
The Moon has many appearances in the sky throughout the course of a month. It may appear as a thin white crescent, a full bright circle, or not appear at all. It may be seen above the horizon in either daytime or nighttime, as its rising and setting time varies. Even the ancients recognized that the Moon is a spherical body, illuminated by the Sun, circling Earth. As it orbits around us every month, we see different portions of the lighted hemisphere, which appear to us as the phases of the Moon.
You can use phone apps such as “Star Walk 2”, “Night Sky”, or “Stellarium” web browser which will show you constellations or other celestial objects in the sky real time. You can even point your phone to the ground to see what celestial objects are visible in the southern hemisphere.
Your assignment:
Over the next few months, observe the Moon through at least one complete cycle of phases (from new/full moon to the next, or first/last quarter to the next etc.)
To give you a start – Full Moon is on Sep 20, 2021 and First quarter is on Oct 13, 2021.
Like the Sun, the Moon is up above the horizon about half of the time. Because it is moving around our planet, the Moon rises about 50 minutes later each night, and its position with respect to the stars in the background constantly changes. That is to say, it moves through the constellations, which themselves do not change. A new moon rises with the Sun, and thus cannot be seen, but as the Moon moves away from the Sun, it stays up later and later each night. Only when full does the moon rise at sunset and stay up all night.
The following table, when completed, may be used to help you know when and where to look for the Moon:
Phase Date Rise time Set time Constellation Nearby stars/planets
New Moon _______ _______ _______ _______ _______
First Quarter _______ _______ _______ _______ _______
Full Moon _______ _______ _______ _______ _______
Last Quarter _______ _______ _______ _______ _______
In addition to the Moon, the planets of our solar system may be visible in the night sky. Mercury, Venus, Mars, Jupiter, and Saturn can be seen with the naked eye at various times of the year. For example, the Moon can be near Venus and/or Mercury as a crescent; and around full Moon, it may be close to planets that are near opposition. They will all be roughly in line with each other, near the ecliptic plane, in the constellations of the zodiac.
Make observations of at least 6 distinct phases(look for due dates on Canvas) as the Moon progresses from new moon, waxing crescent to first quarter, waxing gibbous, full, waning gibbous, last quarter, and waning crescent. You need to have 6 of these phases. For example: I WILL NOT accept 2 waxing gibbous phases with different illumination percentages. Be aware that cloudy weather may interfere with some of your observations, and note that you may need to stay up very late or get up before sunrise at least once.
Observations must be at least 3 days apart to show significant change of the Moon’s phase.
For each observation,
make a sketch of the Moon on a clean, white sheet of paper, including the area of the sky around the Moon, noting prominent stars and constellations, and any other things you observe. One phase/sketch per paper. DO NOT include all the phases on one paper!! (Look at my sample sketch at the top)
Understand that for the scale we chose, the moon’s size is about the size of a dime. Do not draw huge moons!
Draw and label the horizon, with appropriate directions (N, E, S, W, etc.) indicated, along the bottom of each drawing. Your drawing should span about 90° of the horizon, so for example if the center of your drawing is South, the left and right edges should be roughly SE and SW. Clearly label the drawing of each phase.
You will not be graded on artistic ability, but on your ability to make and record a detailed scientific observation. Each Moon sketch MUST include the following for full credit:
Your name, location, date and time of observation (be precise, don’t just say 8:00, say 20:07, or 7:54 p.m PST., or such). Sketches lacking a date or time will have no value
The horizon drawn at the bottom, with the direction you are facing, e.g. E, SE, SW, etc. labeled at bottom center, with the x-axis spanning about 90 degrees in azimuth
a vertical altitude scale along the left edge (y-axis); the horizon is 0°, the zenith is 90°. You can use your fists as a measuring tool to determine how high the moon is from the horizon (Look at the fist measurement below)
prominent stars and constellations, drawn to show their positions (altitude & azimuth) as well as possible (you may use a star chart to identify them by name after sketching)
the Moon (and any planets) in the correct position with respect to the stars you see. Accurately sketch the Moon’s features, paying attention to its size, shape, and rotation (orientation of the terminator, or direction the horns are pointing, if crescent)
include the name of the phase, and any special notes describing the observation, such as weather conditions, color or brightness of stars and planets, your impressions, etc.
At least one of these observations must include a planet: Mercury, Venus, Mars, Jupiter, and/or Saturn. Be aware of the planets’ sizes. You cannot see Saturn’s rings with naked eye observations. Do not draw rings in your sketches or make planets huge!
You should make one observation as soon as possible (i.e. within the next couple of days), and at least 3 more at approximately semi-weekly intervals. Do not procrastinate. This project cannot be done at the last minute. You must catch the Moon; it will not make an appearance just for you!
You could use your hands and fingers to make approximate measurements of height/altitude the moon is from the horizon. A closed fist is about 10 degrees. If you have the moon about 3 vertical closed fists from the horizon, that’s about 30 degrees from the horizon.

In addition to your sketches, answer the following questions (in complete sentences):
These questions must be submitted along with the last submission!
1. Explain what causes the phases. How do the Moon’s rise/set times correlate with phase?
2. Describe what causes a lunar eclipse, and a solar eclipse. When do they happen? Did you see an eclipse? Describe it, or explain why they don’t occur every month.
3. Did the full Moon look larger to you when it was near the horizon? Could you measure (say, by holding up a ruler at arm’s length) any differences between the angular size when it was near the horizon, and the angular size as it rose up overhead? (Try it.)
4. Observe the pattern of darker areas (maria) on the Moon as the phase changes. Do you see the same surface features in the same places? (Bear in mind, things look a bit different when illuminated from different angles.) If the face of the Moon always shows the same features, what does this tell us about the rotation period of the Moon? Is there a Dark Side of the Moon? Can you see it? (If so, indicate it on your sketch.)

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