For this activity, you will be tracking the movement of planets through the sky, much like you did for other celestial objects in Astronomy 1a. One difference in this activity, though, is that you will be measuring how the position of a planet changes relative to a constellation in your view.
Step 1: Choose Your Planet
The planets that will be visible to you depend very much on where you live and what time of year it is. So for this activity, you should do some research to determine which of the following choices of planets will be visible to you: Mercury, Venus, or Mars. For help on which planet(s) are visible when you’re going through this unit, you might consult a site like https://earthsky.org/tonight.
Step 2: Find Your Planet
Sometimes planets can just look like stars in the night sky, so it will be helpful for you to have some more tips on how to find the planet you chose.
Mercury: As viewed from your binoculars, Mercury will appear as a crescent because its orbit is inside of Earth’s.
Venus: As viewed from your binoculars, Venus will also appear as a crescent because its orbit is inside of Earth’s. Venus is usually the brightest object in the night sky (aside from the Moon) so it is best viewed during twilight hours instead of the darker hours of the night, where its glare could make it difficult to focus on.
Mars: Mars will appear red in the sky, especially if you are viewing it through binoculars. It also appears to move quickly through the stars.
After you find your planet, you’ll need to identify a constellation that you can use as a reference point for measuring the planet’s position. Record where the planet is in relation to that constellation, and what time it is.
You will be tracking the movement of the planet for a week. You may want to set up a tracking sheet like this:
TABLE 1 Example
Date Time Location
Step 3: Track Your Planet for a Week
Repeat this process for one week (seven nights of observation). It is okay if you miss a day or two here and there, just make sure you have at least seven entries in your tracking sheet. For example, if you start tracking on Monday but get sick on Tuesday, skip Tuesday and resume on Wednesday. Just make sure your total number of nights tracked is at least seven.
If you use a table like the one in Step 2, then each night note the date in the Date column, the time of your observation in the Time column, and the location of the planet in relation to your constellation of choice in the Location column.
Step 4: Create a Video Presentation Discussing the Movement You Observed
Using a smart phone or other video recorder, create a video of yourself talking through your tracking sheet. Begin with simple descriptions and explanations and then add more details. Your video should be at least 60 seconds long and should cover:
the dates you began and ended observation
the planet and constellation you chose and why you chose each
where the planet first appeared
where it last appeared
how you would describe and explain its movement in between the start and end dates. (For example, sometimes planets move backwards for a few days! Did your planet continue on a straightforward trajectory, or was there something unique about its movement during your tracking period?)
You do not need to add any visuals to your video presentation, unless you feel it will aid in the explanation of your planet’s movement.
To complete this activity, submit your tracking sheet and video file.
