# Natural Science - Year I

#### Unit 10: Planetary Motions

Lab Assignment for Unit 10

 This Unit's Homework Page History Lecture Science Lecture Lab Parents' Notes

# Natural Science Unit 10 Laboratory Activity: Naked Eye Astronomy 2

## Goal: Locate planets and determine their position relative to the sun and the earth.

### Materials and Equipment:

• Open your browser and go to https://stellarium-web.org.
• Click on the location box in the lower left of the display and set your location.
• Click on the date and time box in the lower right and set the time you will observe.
• Grab the display (it defaults to pointing north) and drag it left or right until you can see the south horizon.
• Note which planets are visible and where they are in the sky. Use the "Planets Tonight" option to look at when the planets rise and set if you are observing today.
• Use the options along the bottom to display constellations, alt-azimuth coordinates, and celestial coordinates to see how they might help you find objects or describe their positions.

### Procedure:

#### You should do this activity AFTER you complete the web reading. You will need to do this over several weeks of observing.

1. On four separate nights at least 1 week apart, observe the night sky at approximately the same local solar time (for example, 9 pm standard time. Remember to correct for daylight savings time if it is still in force! 9pm DST = 8pm local solar time).
2. If the moon is visible, locate it in the sky by direction (north, south, southwest, etc.), and note its phase (crescent waxing, gibbous, full).
3. What constellations lie on your west horizon?
4. What constellations lie on your east horizon?
5. What constellations lie on the line from your north point, overhead, to your south point?
6. What is the brightest star near your zenith?
7. What planets are visible? Which constellations are they in?

### Data Analysis:

1. Make a table of your results, with your observations for each date laid out side by side.
2. What general motions can you detect for the moon? Which direction does it move?
3. What general motions can you detect for each planet observed? Which way did it move in the sky (if at all)?
4. Make a map of the solar system for the earth, sun, and the planets you could observe, as seen from high above the earth's north pole. Which direction does each body move around the sun?

### Report:

1. As usual, explain your goals, and describe your materials and equipment.
2. Lay out your results as well as you can. (If you know how to use HTML tables, you can do so in your posting).
3. Describe your map (you do not have to draw this in your posted report).
4. Explain any difficulties you have in reaching conclusions about the actual motions of the sun, earth, moon, and planets based on your observations.