Modern Astronomers and Planetary Motion Review

Newton's Universal Law of Gravity states that force is greatly impacted by mass of the objects and their distance from each other. Which of the following best explains this effect using the formula?

• The force increases with the square of the distance between objects.

• The force decreases with the square of the distance between objects.

• The force is independent of the mass of the objects.

• The force is directly proportional to the distance between objects.

Match the accomplishment/law/theory to the appropriate scientist. A³ = p², A=distance, P= orbital period

• A Copernicus

• B Hubble

• C Newton

• D Kepler

Copernicus

• A Reintroduced the heliocentric model; Established the Copernican Revolution

• B Invented the telescope and named Jupiter’s 4 moons.

• C D³ = (m₁ + m₂)*p² and F=G(mass₁ x mass₂/distance²

• D D³ = p².

Italian astronomer Galileo Galilei discovered the four moons on Jupiter: Io, Europa, Ganymede, and Callisto. Of these four moons, Europa revealed that long linear features on its surface may indicate tidal or tectonic activity. What relevance does this have towards future findings towards habitable zones?

• A young crust

• B highly reflective surface

• C plumes emanating beneath the crust

• D all of the above

He is most famous for his three laws of planetary motion:

• A Tycho Brahe

• B Johannes Kepler

• C Isaac Newton

An ellipse with an eccentricity of zero is

• equal to that of Pluto

• a circle

• similar to that of Mars

• a really flat, elongated ellipse

As you increase the distance of the foci points, what happens to the eccentricity of the ellipse?

• it increases

• it decreases

• it stays the same

• it is closer to zero

When a planet, in its orbit, is closer to the sun, it:

• Moves slower than average.

• Reflects the sunlight less than average.

• Feels less than average gravitational pull.

• Moves faster on average.

In Newton’s Law of Gravity, the force of gravity increases as the:

• mass decreases

• distance increases

• mass increases

How did Kepler's first law of planetary motion alter the Copernican system?

• It changed the perfect circles to ellipses.

• It added epicycles to the perfect circles.

• It placed the Earth at one focus of each orbit.