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Course: High school physics - NGSS > Unit 2
Lesson 2: Activity: Why is a Neptune year so long?Activity: Why is a Neptune year so long?
Make science come alive in your classroom with this free hands-on activity aligned to high school NGSS standards.
Activity: Why is a Neptune year so long?
The planet Neptune takes 165 Earth years to complete one trip around the sun. So, one Neptune year is longer than a human lifetime!
Why does Neptune take so much longer to orbit the sun than Earth does? In this activity, students will collect data for an object moving along a circular path, calculate the gravitational force each planet experiences from the sun, and use patterns to explain why planets have different orbital periods.
Overview
This activity is designed to be completed in two 45-minute class periods, with additional time required for follow-up creative projects. The activity consists of the following parts:
- Setting the stage—Students review the fundamentals of direct and inverse relationships, centripetal force, and orbits. (15 minutes)
- Investigation (Part 1)—Students collect data for an object moving along a circular path to explore the relationship between centripetal force and period. (30 minutes)
- Data analysis (Part 2)—Students use Newton’s law of gravitation to calculate the gravitational force each planet experiences from the sun. Students identify and compare patterns in their data from Parts 1 and 2. Students use their results to explain why Neptune has the longest orbital period of the planets in our solar system. (30 minutes)
- Let's get creative!—Students design a social media post announcing the discovery of an exoplanet. Students include information about the exoplanet's orbital characteristics and how they were determined. (45 minutes)
- Keep creating!—Students can choose from additional project ideas. Each project encourages students to combine scientific knowledge with creativity to produce something new.
Download the worksheets and get started today!
You can print out this activity or upload it to a digital classroom.
- Student activity guide (12 page worksheet)
- Teacher guide (step-by-step instructions)
NGSS performance expectations
HS-PS2-4. Use mathematical representations of Newton’s Law of Gravitation and Coulomb’s Law to describe and predict the gravitational and electrostatic forces between objects.
HS-ESS1-4. Use mathematical or computational representations to predict the motion of orbiting objects in the solar system.
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Want to join the conversation?
Since it takes Neputune 165 years, is there some possibility that if there was life, it would be shrouded in darkness with no light entering?(3 votes)
That's a great thought! The vast distance of Neptune from the Sun means that it receives much less sunlight than planets closer to the Sun. As a result, the surface of Neptune is shrouded in darkness compared to planets like Earth. However, this doesn't necessarily mean that any potential life on Neptune would be completely devoid of light. While sunlight may be significantly dimmer at Neptune's distance, there are other potential sources of light that could support life or ecosystems in its atmosphere or subsurface regions.(4 votes)