Movements in Space

Which answer best states the differences between a total lunar eclipse and a total solar eclipse?

• A total lunar eclipse occurs when Earth moves within the shadow cast directly behind the moon. A total solar eclipse occurs when the moon moves within the shadow cast directly behind Earth.

• A total solar eclipse occurs when Earth moves within the shadow cast directly behind the moon. A total lunar eclipse occurs when the moon moves within the shadow cast directly behind Earth.

• A total lunar eclipse occurs when Earth moves just beyond the shadow cast directly behind the moon. A total solar eclipse occurs when the moon moves just beyond the shadow cast directly behind Earth.

• A total solar eclipse occurs when Earth moves just beyond the shadow cast directly behind the moon. A total lunar eclipse occurs when the moon moves just beyond the shadow cast directly behind Earth.

Planet A and planet B both orbit the same star, but planet A is twice as far from the star as planet B is. A student argues that planet A takes exactly twice as long as planet B to orbit the star. Is the student correct?

• Yes. Planet A and planet B both travel at the same velocity. Therefore, planet A takes exactly twice as long as planet B to orbit the star.

• No. Planet A travels more quickly than planet B. Therefore, planet A takes less than twice as long as planet B to orbit the star.

• No. Planet A travels more slowly than planet B. Therefore, planet A takes more than twice as long as planet B to orbit the star.

• Any of the above could be true; the answer depends on the planets' respective masses.

Which of the following is not a phase of the moon?

• first quarter

• waning quarter

• waxing crescent

• waxing gibbous

Which of the following is the primary cause of tides on Earth?

• Earth's rotation on its axis

• the moon's revolution around Earth

• Earth's revolution around the Sun

• Earth's position between Venus, which is more massive, and Mars, which is less massive

When a satellite always keeps the same side toward the object is orbiting, the satellite is _________________.

• artificial

• natural

• axially tilted

• tidally locked

According to Kepler's first law of planetary motion, ____________.

• a planet's orbit is circular, with the Sun at the center of the circle.

• a planet's orbit is elliptical, with The Sun at the center of the ellipse.

• a planet's orbit is elliptical, with the Sun at one focus of the ellipse.

• a planet's orbit is elliptical, with the Sun moving back and forth between the ellipse's two foci.

Planet A, planet B, and planet C all have equal masses. Planet A is located between planets B and C, but planet B is twice as far away from planet A as planet C is. Which planet exerts the greater gravitational pull on planet A?

• planet B

• planet C

• Both planets exert the same gravitational pull on planet A.

• Any of the above could be true; the answer depends whether planet A is tilted toward planet B or planet C.

Which of the following is the primary cause of seasons on Earth?

• the gravitational pull by the moon on Earth

• the gravitational pull by the Sun on Earth

• Earth's axial tilt as it revolves around the Sun

• the moon's axial tilt as it revolves around Earth

Which of the following natural phenomena is partly caused by Earth's revolution around the Sun?

• eclipses only

• seasons only

• solstices only

• eclipses, seasons, and solstices

A student argues that because earth is closest to the Sun at perihelion, all of Earth experiences summer at perihelion. Is the student correct?

• Yes. All of Earth experiences summer at perihelion.

• No. Earth is farthest from the Sun at perihelion. Therefore, all of Earth experiences winter at perihelion.

• No. Although Earth is closest to the Sun at perihelion, only the hemisphere tilted toward the sun experiences summer.

• No. Earth is farthest from the Sun at perihelion. In addition, only the hemisphere tilted toward the Sun experiences summer.