---

This Unit's

Homework Page

History Lecture

Science Lecture

Lab

Parents' Notes

For 2026: Please note that units are considered "under revision" until two weeks before the class date, and page content, web assignments, and exercises may change before that deadline.

Natural Science Unit 4 Laboratory Activity:
Naked Eye Astronomy

Goal: Observing the Moon

Materials and Equipment:

Naked eye: we are looking for location of the moon in the sky, not features on the moon. Paper and pencil.

Procedure:

During a two week period, observe the location and time of the moon's rising on your eastern horizon for as many nights as you can. Estimate the altitude and azimuth of the moon at the time it rises, and use the background stars to estimate its right ascension and declination.

Note: the moon is full on September 26, when it rises as the sun sets with the sun, and new on October 10 when it rises around sunset. For October 2026, the best observing times will be between October 3 when the moon is in third quarter and setting before the sun sets, and October 18, when the moon is in first quarter and bright enough to interfere with evening observations.

Data Analysis:

Create a table for your observations. Determine how much later the moon rises each night according to the clock, and then determine the difference in Right Ascension. Are these values the same? Why or Why not?

Use your data to determine the location and time of the rising of the moon for several nights into the future, then check at least one of your predictions. How accurate was it?

Report:

Follow your teacher's instructions for how and where to send your lab reports. Your written report should include

• Your observing location (city and state, latitude and longitude)
• Your observing conditions (clear, somewhat hazy, dark sky, light sky)
• The dates and times of your observations
• The difference in position and appearance of the moon on each night.
• You prediction for the rising time of the moon 1 night after your last observation and 5 nights after your last observation.

---

© 2005 - 2026 This course is offered through Scholars Online, a non-profit organization supporting classical Christian education through online courses. Permission to copy course content (lessons and labs) for personal study is granted to students currently or formerly enrolled in the course through Scholars Online. Reproduction for any other purpose, without the express written consent of the author, is prohibited.