Gravity in Our Solar System

According to the law of universal gravitation, any two objects are attracted to each other. The strength of the gravitational force depends on the masses of the objects and their distance from each other. Many stars have planets around them. If there were no gravity attracting a planet to its star, the planet's motion would carry it away from the star. However, when this motion is balanced by the gravitational attraction to the star, the planet orbits the star. Two solar systems each have a planet the same distance from the star. The planets have the same mass, but Planet A orbits a more massive star than Planet B. Which of the following statements is true about the planets?

• Planet A orbits its star faster than Planet B.

• Planet A has a longer year than Planet B.

• Planet B is more attracted to its star than Planet A.

• Planet B will keep orbiting its star longer than Planet A

Tags

NGSS.MS-ESS1-2

NGSS.MS-PS2-4

Why does the Sun gravitationally dominate all other objects in the Solar System?

• The Sun is by far the brightest object in the Solar System.

• The Sun is by far the most massive object in the Solar System.

• The Sun moves at a greater speed than any of the other objects in the Solar System.

• The Sun is the closest object to planet Earth.

Tags

NGSS.MS-ESS1-2

NGSS.MS-PS2-4

Gravity keeps

• the planet Mars in orbit around the Sun.

• moons in orbit around the planet Saturn.

• the Moon in orbit around Earth.

• all of these

Tags

NGSS.MS-ESS1-2

NGSS.MS-PS2-4

A scientist observes and records data for the force of gravity between the Sun and a few different-sized planets. The different-sized planets are placed at the same distance from the Sun. Based on the above scenario, which graph best represents the gravity between the different-sized planets and the Sun?

• Z

• Y

• X

• W

Tags

NGSS.MS-PS2-4

What is the primary force that governs the motion of planets in the Solar System?

• Electromagnetic force

• Gravity

• Nuclear force

• Friction

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DOK Level 1: Recall

NGSS.MS-ESS1-2

Which of the following statements about gravity in the Solar System is true?

• Gravity only affects the planets.

• Gravity is stronger on smaller planets.

• Gravity keeps the planets in orbit around the Sun.

• Gravity does not affect asteroids.

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DOK Level 2: Skill/Concept

Develop a model to describe the role of gravity in the motion of planets within the Solar System. Include the Sun and at least two planets in your model.

• A model showing planets moving in straight lines away from the Sun.

• A model showing planets orbiting the Sun in elliptical paths due to gravitational pull.

• A model showing planets stationary in space.

• A model showing planets moving randomly in space.

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DOK Level 3: Strategic Thinking

NGSS.MS-ESS1-2

Which of the following best describes how gravity affects the motion of objects in the Solar System?

• Gravity only affects objects on Earth.

• Gravity pulls objects towards the center of the Earth.

• Gravity keeps planets in orbit around the Sun.

• Gravity has no effect on the motion of objects in space.

Tags

DOK Level 2: Skill/Concept

NGSS.MS-ESS1-2

Which of the following statements is true about the role of gravity in the Solar System?

• Gravity only affects the motion of the Sun.

• Gravity affects the motion of all objects in the Solar System.

• Gravity only affects the motion of planets.

• Gravity has no effect on the motion of objects in the Solar System.

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DOK Level 1: Recall

NGSS.MS-ESS1-2

Using evidence, explain how gravity has influenced the formation and evolution of the Solar System.

• Gravity had no role in the formation of the Solar System.

• Gravity caused the collapse of a molecular cloud, leading to the formation of the Sun and planets.

• Gravity only affects the motion of planets after they are formed.

• Gravity prevents the formation of planetary systems.

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DOK Level 4: Extended Thinking

NGSS.MS-ESS1-2