Astronomy 300. The Cosmic Perspective Fundamentals Chapter 3-4

Leftover ice-rich planetesimals are called A) asteroids. B) meteors. C) comets.

C) comets.

Which of the following is not true about a scientific theory? A) A theory is essentially an educated guess. B) Even the strongest theories can never be proved true beyond all doubt. C) A theory must explain a wide range of observations or experiments.

A) A theory is essentially an educated guess.

Why didn't a terrestrial planet form at the location of the asteroid belt? A) Jupiter's gravity kept planetesimals from accreting into a planet there. B) There was never enough material in that part of the solar nebula. C) The solar wind cleared away nebular material there.

A) Jupiter's gravity kept planetesimals from accreting into a planet there.

Which of the following kinds of object resides closest to the Sun on average? A) asteroids B) jovian planets C) comets

A) asteroids

Which of the following changes did not occur during the collapse of the solar nebula? A) concentrating denser materials nearer the Sun B) heating up C) spinning faster

A) concentrating denser materials nearer the Sun

In which list are the major steps of solar system formation in the correct order? A) gravitational collapse of the solar nebula, condensation, accretion B) gravitational collapse of the solar nebula, accretion, condensation C) accretion, condensation, gravitational collapse of the solar nebula

A) gravitational collapse of the solar nebula, condensation, accretion

When Einstein's theory of gravity (general relativity) gained acceptance, it demonstrated that Newton's theory had been A) incomplete. B) really only a guess. C) wrong.

A) incomplete.

The largest terrestrial planet and jovian planet are, respectively, A) Venus and Jupiter. B) Earth and Jupiter. C) Earth and Pluto.

B) Earth and Jupiter.

Earth is closer to the Sun in January than in July. Therefore, in accord with Kepler's second law, A) Earth travels faster in its orbit around the Sun in July than in January. B) Earth travels faster in its orbit around the Sun in January than in July. C) it is summer in January and winter in July.

B) Earth travels faster in its orbit around the Sun in January than in July.

What's the leading theory for the origin of the Moon? A) It split off from a rapidly rotating Earth. B) It formed from the material ejected by a giant impact on Earth. C) It formed at the same time as Earth.

B) It formed from the material ejected by a giant impact on Earth.

Which of the following was not a major advantage of Copernicus's Sun-centered model over the Ptolemaic model? A) It allowed calculation of the orbital periods and distances of the planets. B) It made significantly better predictions of planetary positions in our sky. C) It offered a more natural explanation for the apparent retrograde motion of planets in our sky.

B) It made significantly better predictions of planetary positions in our sky.

How many of the planets orbit the Sun in the same direction that Earth does? A) a few B) all C) most

B) all

Tycho Brahe's contribution to astronomy included A) proving that Earth orbits the Sun. B) collecting data that enabled Kepler to discover the laws of planetary motion. C) inventing the telescope.

B) collecting data that enabled Kepler to discover the laws of planetary motion.

Which ingredients made up about 98% of the solar nebula? A) hydrogen compounds B) hydrogen and helium C) rock and metal

B) hydrogen and helium

Galileo's contribution to astronomy included A) discovering the laws of planetary motion. B) making observations and conducting experiments that dispelled scientific objections to the Sun-centered model. C) discovering the law of gravity.

B) making observations and conducting experiments that dispelled scientific objections to the Sun-centered model.

If Earth were twice as far as it actually is from the Sun, the force of gravity attracting Earth to the Sun would be A) half as strong. B) one-quarter as strong C) twice as strong.

B) one-quarter as strong

About how old is the solar system? A) 4.5 million years B) 4.5 trillion years C) 4.5 billion years

C) 4.5 billion years

According to Kepler's third law, A) Mercury travels fastest in the part of its orbit in which it is closest to the Sun. B) all the planets have elliptical orbits. C) Jupiter orbits the Sun at a faster speed than Saturn.

C) Jupiter orbits the Sun at a faster speed than Saturn.

Which of the following is not true about scientific progress? A) Science progresses through the creation and testing of models of nature. B) Science avoids explanations that invoke the supernatural. C) Science advances only through strict application of the scientific method.

C) Science advances only through strict application of the scientific method.

Kepler made a major break from ancient beliefs when he A) decided to look for a system that could explain actual observations. B) realized that gravity holds the planets in their orbits. C) abandoned circular orbits in favor of elliptical orbits

C) abandoned circular orbits in favor of elliptical orbits

A geocentric model of the universe is A) any model that places the Sun at the center of the universe. B) any model that has Earth as a planet orbiting the Sun. C) any model that places Earth at the center of the universe.

C) any model that places Earth at the center of the universe.

Planetary orbits are A) fairly circular but oriented in random directions. B) very eccentric (stretched out) ellipses and in the same plane. C) fairly circular and in the same plane.

C) fairly circular and in the same plane.

Which have more moons on average? A) terrestrial planets B) Terrestrial and jovian planets both have about the same number of moons. C) jovian planets

C) jovian planets

In Ptolemy's geocentric model, the retrograde motion of a planet occurs when A) Earth is about to pass the planet in its orbit around the Sun. B) the planet is aligned with the Moon in our sky. C) the planet actually goes backward in its orbit around Earth.

C) the planet actually goes backward in its orbit around Earth.