Name______Class______Date______

18-1 Section: Astronomy: The Original Science

1.In what way did people in ancient cultures mark the passage of time? ______

2.What science did the study of the night sky eventually become? ______

OUR MODERN CALENDAR

Match the correct definition with the correct term. Write the letter in the space provided.

______3.roughly the amount of time required for the moon to orbit once around the Earth

______4.the time required for the Earth to orbit once around the sun

______5.the time required for the Earth to rotate once on its axis

WHO’S WHO OF EARLY ASTRONOMY

______6.Most early astronomers thought that the universe consisted of

a.the sun and the Earth. b. the sun and the planets.

c.the sun, the moon, and the planets. d. the sun, the moon, and the Earth.

______7.What was Ptolemy’s theory of the universe?

a.The Earth was at the center of the universe, and the sun, moon, and other planets revolved around it.

b.The sun was at the center of the universe, and the Earth and the other planets revolved around it.

c.The sun and the moon revolved around the Earth, but the other planets revolved around the sun.

d.The planets revolved around the sun in elliptical orbits.

______8.How long did Ptolemy’s Earth-centered theory remain the popular theory for the structure of the universe?

a.about 100 years b. about 500 years

c.over 1,500 year d. over 5,000 years

______9.Why was Ptolemy’s theory of the universe helpful even though it was incorrect? ______

______10.What was Copernicus’s theory of the universe? ______

______11.Which astronomer’s theory led to major changes in science and society?

a.Hubble b. Brahe

c.Ptolemy d. Copernicus

______12.What was Brahe’s theory of the universe? ______

______13.Why was Brahe’s work helpful even though his theory of the universe was incorrect?

a.He accurately described the planets’ orbits. b.He made detailed measurements of the sun.

c.He explained the sun’s role in the universe. d.He made very precise observations of the planets and stars.

______14.What did Kepler believe about the universe? ______

______15.What laws did Kepler state that are still in use today?

a.laws of planetary names b. laws of planetary motion

c.laws of solar motion d. laws of gravity

______16.Who was one of the first scientists to use a telescope? ______

17.What four discoveries did Galileo make that showed planets are physical bodies like the Earth and not “wandering stars”?

______

18.What did Newton prove about gravity? ______

19.Newton’s laws of motion and gravity helped to explain many other scientists’ observations. For example, what law announced by Kepler was supported by Newton’s laws? ______

modern ASTRONOMY

20.What were two milestones in the development of modern astronomy? ______

21.What did many astronomers believe about galaxies prior to the 1920s? ______

22.What did Edwin Hubble prove in 1924? ______

23.What belief of other astronomers did Edwin Hubble’s discovery confirm? ______

20-4 Section: Planetary Motion

A revolution in astronomy

1.How does Earth’s rotation determine whether it is day or night? ______

Match the correct definition with the correct term. Write the letter in the space provided.

______2.the spinning of a body on its axis

______3.the path a body follows as it travels around another body in space

______4.a complete trip along an orbit

______5.the time it takes a planet to complete a single trip around the sun

6.According to Kepler’s first law of motion, planets move in a(n) ______around the sun.

7.The maximum length of an ellipse, or a planet’s orbit, is called its______.

8.A planet’s maximum distance from the sun is the ______of its orbit.

9.According to Kepler’s second law of motion, how does a planet’s distance from the sun affect its motion?

10.According to Kepler’s third law of motion, what information can be used to find a planet’s distance from the sun?

______11.What causes the planets that are closer to the sun to move faster?

a.gravity b. heat

c.magnetic fields d. solar energy

______12.Newton discovered that the force of gravity depends on the distance between objects and the objects’

a.volume. b. circumference.

c.shape. d. mass.

______13.The force of gravity between two objects increases if

a.they have smaller masses and are farther apart.b.they have smaller masses and are closer together.

c.they have larger masses and are farther apart .d.they have larger masses and are closer together.

______14.An object’s resistance in speed or direction is called ______

______15.Gravity causes bodies in the solar system to

a.repel one another. b. fall in a straight path.

c.stay in orbit. d. move in a circular path.
21-4 Section: Moons

1.Natural or artificial bodies that revolve around larger bodies such as planets are called ______.

2.Except for Mercury and Venus, all of the planets have natural satellites called ______.

3.What is the difference between a moon and a satellite? ______
Luna: The Moon of Earth

______4.How old were the lunar rocks brought back by the Apollo missions?

a.3 billion years b. about 3.8 billion years

c.about 4.6 billion years d. more than 5 billion years

5.What does the age of these rocks tell us about our solar system? ______

6.What happens to impacts on the surface of bodies without an atmosphere? ______

7.What were the three popular explanations for the moon’s formation? ______
______

8.What is the current theory about the origin of the moon? ______
9.What evidence supports the current theory about the origin of the Moon?

10.Describe how the moon’s appearance changes during the month. ______
11.___The different appearances of the moon due to its changing position are called ______.

12.What causes the different appearances of the moon? ______

13.Why do we always see the same side of the moon from Earth? ______

14.When the moon is ______, the sunlit part of the moon that we can see is getting larger. When the moon is ______the sunlit part of the moon that we can see is getting smaller.

Match the correct description with the correct term. Write the letter in the space provided.

______15.when the moon’s shadow falls on part of the Earth

______16.when the shadow of Earth falls on the moon

______17.when the shadow of one celestial body falls on another

______18.when a thin solar ring is visible around the edge of the moon

______19.when the moon’s disk completely covers the sun

20.Why don’t we see solar and lunar eclipses every month? ______

______21.Which of the following statements about moons in this solar system is NOT correct?

a.Some orbit their planet backwards. b. Many may be captured asteroids.

c.Some have very elongated orbits. d. None is as large as the terrestrial planets.

______22.Why do scientists think the Martian moons may be asteroids caught by the planet’s gravity?

a.They are very small moons. b. They are very dark.

c.They are similar in composition. d. They are oddly shaped.

______23.Who discovered the four largest moons of Jupiter?

a.Copernicus b. Galileo

c.Ganymede d. Mercury

25.What evidence supports the idea that life could have evolved on Europa? ______

26.Why might Titan hold the key to learning more about the origin of life? ______

20-2 Section: The Sun: Our Very Own Star

______1.The sun is a large ball of gas made mostly of

a.oxygen and carbon. b. hydrogen and helium.

c.nitrogen and sulfur. d. carbon dioxide and oxygen.

______8.Early scientists thought that the sun produced its energy by

a.rotating. b. expanding.

c.collapsing inward. d. burning fuel.

______10.Albert Einstein showed that matter and energy are

a.the same. c. unchanging.

b.opposites. d. interchangeable.

______11.What formula did Einstein use to show the relationship between matter and energy?

a.E = mc c. M = ec

b.E = mc2 d. M = ec2

______12.Einstein’s formula states that energy equals mass times the

a.speed of light. b. square of the speed of light.

c.fusion of hydrogen. d. fusion of helium.

13.The process by which two or more low-mass nuclei combine to form another nucleus is called ______.

14.What happens as four hydrogen nuclei fuse? ______

15.Energy is produced in the center, or ______, of the sun.

______19.The circulation of gases in the sun combines with the sun’s rotation to create

a.heat. b. radiation.

c.electric fields. d. magnetic fields.

20.Why do some areas of the photosphere become cooler than surrounding areas?

21.Cooler, dark areas of the photosphere of the sun are called ______.

22.The sunspot cycle lasts about ______years.

23. How might sunspot activity affect Earth? ______

24.Regions of very high temperature and brightness on the sun’s surface are called______.

25.How might Earth be affected by the eruption of solar flares? ______

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