Astronomy: Exam 1, Chapter 3

Which of these (hypothetical) modifications would cause lunar eclipses to happen once per month? Relocate the Moon to twice its current distance from the Earth. Make the Moon orbit the Earth twice as fast. Change the Moon's orbital plane so it tilts the opposite way. Change the orbital plane of the Moon so it lies in the same plane as Earth's orbit around the Sun.

Change the orbital plane of the Moon so it lies in the same plane as Earth's orbit around the Sun.

During a lunar eclipse the Moon's phase must be 3rd quarter. new. full. 1st quarter.

full

Which statement correctly describes the way the planet sizes are shown compared to their orbits? Hints Jupiter is shown correctly to scale with its orbit, but all the other planets are too large. The planets should all be about twice as large as shown. The planets are all much too large compared to their orbits. The planet sizes are correctly shown on the same scale as the orbits.

The planets are all much too large compared to their orbits.

If we have a new moon today, when we will have the next full moon? in about 1 week in about 1 month in about 6 months in about 2 weeks

in about 2 weeks

He angered the Pope with his assertions that the Earth moved around the Sun. Galileo Tycho Copernicus Kepler

Galileo

Kepler's second law states that as a planet orbits the Sun, it sweeps out equal areas in equal times. Which of the following statements describe a characteristic of the solar system that is explained by Kepler's second law? Inner planets orbit the Sun at higher speed than outer planets. Earth is slightly closer to the Sun on one side of its orbit than on the other side. Pluto moves faster when it is closer to the Sun than when it is farther from the Sun. All the planets orbit the Sun in nearly the same plane. Venus orbits the Sun faster than Earth orbits the Sun. The Sun is located slightly off-center from the middle of each planet's orbit.

Pluto moves faster when it is closer to the Sun than when it is farther from the Sun.

Kepler's first law states that the orbit of each planet is an ellipse with the Sun at one focus. Which of the following statements describe a characteristic of the solar system that is explained by Kepler's first law? The Sun is located slightly off-center from the middle of each planet's orbit. All the planets orbit the Sun in nearly the same plane. Inner planets orbit the Sun at higher speed than outer planets. Pluto moves faster when it is closer to the Sun than when it is farther from the Sun. Earth is slightly closer to the Sun on one side of its orbit than on the other side. Venus orbits the Sun faster than Earth orbits the Sun.

The Sun is located slightly off-center from the middle of each planet's orbit. Earth is slightly closer to the Sun on one side of its orbit than on the other side.

All of the following statements are true. Which one can be explained by Kepler's third law? Mars moves faster in its orbit when it is closer to the Sun than when it is farther from the Sun. Venus orbits the Sun at a faster orbital speed than Earth. Earth is slightly closer to the Sun in January than in July. All the planets orbit the Sun in nearly the same plane. The Sun is not in the precise center of Saturn's orbit.

Venus orbits the Sun at a faster orbital speed than Earth

Kepler's second law, which states that as a planet moves around its orbit it sweeps out equal areas in equal times, means that a planet's period does not depend on the eccentricity of its orbit. planets have circular orbits. the period of a planet does not depend on its mass. a planet travels faster when it is nearer to the Sun and slower when it is farther from the Sun. planets that are farther from the Sun move at slower average speeds than nearer planets.

a planet travels faster when it is nearer to the Sun and slower when it is farther from the Sun.

Why did Ptolemy have the planets orbiting Earth on "circles upon circles" in his model of the universe? to explain why the Greeks were unable to detect stellar parallax to properly account for the varying distances of the planets from Earth to explain why Venus goes through phases as seen from Earth to explain the fact that planets sometimes appear to move westward, rather than eastward, relative to the stars in our sky to explain why more distant planets take longer to make a circuit through the constellations of the zodiac

to explain the fact that planets sometimes appear to move westward, rather than eastward, relative to the stars in our sky

Earth is slightly closer to the Sun in January than in July. How does the area swept out by Earth's orbit around the Sun during the 31 days of January compare to the area swept out during the 31 days of July? Both areas are the same. The area swept out in January is larger. The area swept out in July is larger.

Both areas are the same.

Galileo challenged the idea that objects in the heavens were perfect by ________. observing sunspots on the Sun and mountains on the Moon inventing the telescope showing that heavy objects fall at the same rate as lighter objects proving Kepler's laws were correct

observing sunspots on the Sun and mountains on the Moon

he Milky Way shows itself as a blurry circle of light in the sky because the Sun is at the center of the Milky Way Galaxy. The galaxy is a flat disk of stars appearing as a blurry band or ring of stars and dust in the sky, all seen at great distances. the spinning Earth blurs the stars above its equator onto this faint circle of blurry starlight and dust. it is a ring-like structure of stars and dust located hundreds of thousands of light-years from Earth. It is blurry because it is so far away. we are looking along the plane of our galaxy that is filled with stars. When we look in other directions, we see fewer stars because we are looking through (at a steep angle to) the plane of our galaxy. We actually see only a small fraction of the stars of the Milky Way Galaxy.

we are looking along the plane of our galaxy that is filled with stars. When we look in other directions, we see fewer stars because we are looking through (at a steep angle to) the plane of our galaxy. We actually see only a small fraction of the stars of the Milky Way Galaxy.

Earth is farthest from the Sun in July and closest to the Sun in January. During which Northern Hemisphere season is Earth moving fastest in its orbit? spring winter fall summer

winter

Kepler's Third Law relates a planet's orbital period (p) and its average distance (a) from the Sun . If a planet were discovered with an average distance from the Sun of 100 AU, its period would be 10,000 years. 1000 years. Not enough information to say. 1 million years.

1000 years

Jupiter orbits the Sun at an average distance of 5.203 AU and takes 11.86years to complete each orbit. Based on these facts, which statement is true? Jupiter's orbital period is 5.2032 times Earth's orbital period. 5.2032=11.863 11.862=5.2033 Jupiter's orbital period is 5.2033 times Earth's orbital period.

11.862=5.2033

The controversial book On the Revolutions of the Celestial Spheres of this famous person, published in 1543 (the year of his death), suggested that Earth and other planets orbit the Sun. Copernicus Ptolemy Kepler Galileo Tycho Brahe

Copernicus

When Copernicus first created his Sun-centered model of the universe, it did not lead to substantially better predictions of planetary positions than the Ptolemaic model. Why not? Copernicus placed the planets in the wrong order going outward from the Sun. Copernicus placed the Sun at the center, but did not realize that the Moon orbits the Earth. Copernicus misjudged the distances between the planets. Copernicus used perfect circles for the orbits of the planets.

Copernicus used perfect circles for the orbits of the planets.

Suppose a comet orbits the Sun on a highly eccentric orbit with an average (semimajor axis) distance of 1 AU. How long does it take to complete each orbit, and how do we know? Each orbit should take about 2 years, because the eccentricity is so large. It depends on the eccentricity of the orbit, as described by Kepler's first law. It depends on the eccentricity of the orbit, as described by Kepler's second law. Each orbit takes about 1 year, which we know from Kepler's third law.

Each orbit takes about 1 year, which we know from Kepler's third law.

Failing to predict this planet's orbit so frustrated Kepler that it led him to consider an ellipse, rather than a circle, as the shape of a planet's orbit. Venus Jupiter Mars Saturn

Mars

All of the following statements are true. Which one can be explained by Kepler's second law? All the planets orbit the Sun in nearly the same plane. The Sun is not in the precise center of Saturn's orbit. Mars moves faster in its orbit when it is closer to the Sun than when it is farther from the Sun. Venus orbits the Sun at a faster orbital speed than Earth. Earth is slightly closer to the Sun in January than in July.

Mars moves faster in its orbit when it is closer to the Sun than when it is farther from the Sun.

Which of the following conditions must exist for a solar eclipse to occur? The only condition is that the phase of the Moon must be new. Moon phase is full, and the Moon is passing through the Earth's orbital plane. Moon phase is new, and the Moon is passing through the Earth's orbital plane. The only condition is that the phase of the Moon must be full.

Moon phase is new, and the Moon is passing through the Earth's orbital plane.

Which of the following statements about constellations is false? It is possible to see all the constellations from Earth's equator. There are only 88 official constellations. Some constellations can be seen in both the winter and summer. Most constellations will be unrecognizable hundreds of years from now. Some constellations can be seen from both the Northern and Southern hemispheres.

Most constellations will be unrecognizable hundreds of years from now.

You discover an asteroid that orbits the Sun with the same 1-year orbital period as Earth. Which of the following statements must be true? The asteroid has a more eccentric orbit than Earth. The asteroid shares the same orbit around the Sun as Earth. The asteroid has the same perihelion distance as Earth. The asteroid will eventually collide with Earth. The asteroid's average (semimajor axis) distance from the Sun is 1AU.

The asteroid's average (semimajor axis) distance from the Sun is 1AU.

Why were ancient peoples unable to detect stellar parallax? They could not see distant stars. They did not look for it. They did not observe for long enough periods of time. They did not have the ability to measure very small angles. They did detect it, but they rejected the observations.

They did not have the ability to measure very small angles.

Why did the Greeks conclude that the Earth was stationary, and that the Sun and the planets orbited around the Earth? They knew that everything in the heavens had to be a perfect circle. They did not observe any change in the separation of stars during Earth's orbit. They felt that the Sun was really the god Apollo. They did not understand the concept of stellar parallax.

They did not observe any change in the separation of stars during Earth's orbit.

Kepler's third law states that a planet's orbital period, p, is related to its average (semimajor axis) orbital distance, a, according to the mathematical relationship p2=a3. Which of the following statements describe a characteristic of the solar system that is explained by Kepler's third law? All the planets orbit the Sun in nearly the same plane. Earth is slightly closer to the Sun on one side of its orbit than on the other side. Pluto moves faster when it is closer to the Sun than when it is farther from the Sun. Venus orbits the Sun faster than Earth orbits the Sun. Inner planets orbit the Sun at higher speed than outer planets.

Venus orbits the Sun faster than Earth orbits the Sun. Inner planets orbit the Sun at higher speed than outer planets.

Consider the elliptical orbit of a comet around the Sun. Where in its orbit is the comet moving the fastest? It is always moving at the same speed. When it is farthest from the Sun. When it is closest to the Sun.

When it is closest to the Sun.

Suppose you live in the United States and you see a crescent moon in your evening sky tonight. What will a friend in South America see tonight? Your friend won't see the Moon tonight, because it is up only in the morning. Your friend will see a gibbous moon. Your friend will see a first quarter moon. Your friend will also see a crescent moon.

Your friend will also see a crescent moon.

From Kepler's third law, a hypothetical planet that is twice as far from the Sun as Earth should have a period of 2 Earth years. more than 2 Earth years. 1 Earth year. 1/2 Earth year. It depends on the planet's mass.

more than 2 Earth years.