8th grade science Earth and Moon

Topic 6 Study guide for 8th grade Savvas, teacher made test questions.

Term: What is a meteor?

Definition: A streak of light produced when a small piece of rock or ice burns up as it enters Earth’s atmosphere.

Term: What is a meteorite?

Definition: A meteor that survives its passage through Earth’s atmosphere and strikes the ground.

Term: Which one presents as a streak of light across the night sky?

Definition: Meteor.

What are the phases of the moon?

Definition: New moon, Waxing crescent, First quarter, Waxing gibbous, Full moon, Waning gibbous, Third quarter, Waning crescent.These are the eight distinct phases as the moon orbits the Earth.

Term: Which phase or phases would the moon be in when a neap tide is produced?

First and third quarter.

Term: What is the result from gravitational differences in how Earth, the moon, and the sun interact at different alignments?

Definition: Tides.

Explain how the alignments of the sun, moon, and Earth cause the different phases of the moon.

Definition: As the Earth-moon system orbits the sun, half of the moon is always lit by the sun. Because the moon orbits around Earth, the side of the moon that is lit is not always directly facing Earth. The phases occur when different amounts of the lit side of the moon are visible from Earth.

Term: What is the band/plane called where planets orbit the sun?

Definition: Zodiac.

Term: What causes seasonal differences in temperature as Earth revolves around the sun?

Definition: The tilt of Earth’s axis.

Term: In Alaska, why does the sun never completely set in the summer?

Definition: In summer, the northern hemisphere is tilted toward the sun, causing prolonged sunlight, which allows the sun to circle the sky without setting.

Term: Which object was at the center of Aristotle and Ptolemy’s model of the solar system?

Definition: Earth.

Term: What are the two forces that keep the moon in orbit around Earth?

Definition: Gravity attracts the moon toward Earth, and inertia keeps the moon in motion.

Term: What is an axis?

Definition: An imaginary line that passes from the north pole, through Earth’s center, to the south pole.

Term: What is a solstice?

Definition: The only day per year when the sun appears highest in the sky in each hemisphere.

Term: What is a comet?

Definition: A cold mixture of dust and ice that develops a long trail of light as it approaches the sun.

Term: What is an ellipse?

Definition: An oval shape, which may be elongated or nearly circular; the shape of the planets’ orbits.

Term: What is the umbra?

Definition: During an eclipse, the very darkest part of the shadow where the light from the sun is completely blocked.

Term: What is the penumbra?

Definition: The area of the shadow where the sun is only partially blocked.