Question 1

In the ________ model of the Solar System, ________ motion is only an apparent, not a real, motion.

Accepted Answer

The answer of In the ________ model of the Solar...

Question 2

If the synodic period of Mars is observed from Earth to be 2.1 years, what is Mars's sidereal period?

Accepted Answer

The synodic period is the time it takes for a planet to return to the same position relative to the sun and Earth. The sidereal period is the time it takes for a planet to complete one orbit around the sun relative to the distant stars. Therefore, we can use the equation 1/P = 1/S - 1/E, where P is the synodic period, S is the sidereal period, and E is Earth's sidereal period (1 year). Plugging in the given values, we get 1/S = 1/2.1 - 1/1 = 0.4762. Solving for S, we get S = 1/0.4762 = 2.1 years. Therefore, the answer is choice C, 1.9 years.

Question 3

Observations of what astronomical events allowed astronomers to definitively determine that the heliocentric model of the solar system was correct?

Accepted Answer

The precise motions of planets across the celestial sphere were observed and measured by astronomers, ultimately providing evidence for the heliocentric model. Specifically, the retrograde motion of planets was better explained by a heliocentric model rather than a geocentric one.

Question 4

The time it takes for a planet to come back to the same position relative to the Sun is called its _________ period.

Accepted Answer

Synodic period refers to the time it takes for a planet to return to the same position relative to the Sun as observed from Earth, and takes into account the changing positions of both Earth and the planet in their respective orbits. Sidereal period refers to the time it takes for a planet to return to the same position relative to the fixed stars, not taking into account Earth's orbit around the Sun. Heliocentric and geocentric refer to the positioning of the Sun and Earth, respectively, and do not relate to the orbital period of a planet. Prograde refers to the direction of a planet's rotation or orbit, and does not relate to its period.

Question 5

The fact that Kepler's heliocentric model of the Solar System predicted _________ more easily and accurately than the geocentric model is an illustration of how scientific theories evolve by the scientific method.

Accepted Answer

Kepler's heliocentric model accurately predicted the retrograde motion of planets, which was difficult to explain in the geocentric model.

Question 6

When the Sun, the Earth, and a planet all lie along a straight line, the planet is at:

Accepted Answer

When the Sun, the Earth, and a planet all lie along a straight line, the planet is either at opposition or conjunction. Opposition occurs when the planet is on the opposite side of Earth from the Sun, while conjunction occurs when the planet is on the same side of the Sun as Earth. Therefore, the best choice is E, either opposition or conjunction.

Question 7

If the synodic period of Venus is observed from Earth to be 1.6 years, Venus' sidereal period is _____ years.

Accepted Answer

The synodic period (S) and sidereal period (P) of a planet are related by the formula: 1/S = 1/P - 1/E, where E is Earth's sidereal period (1 year). For Venus, 1/1.6 = 1/P - 1/1. Solving for P gives P = 0.62 years.

Question 8

The amount of time a planet takes to orbit the Sun is called its _________ period.

Accepted Answer

Sidereal period is the amount of time a planet takes to complete one full orbit around the Sun measured with respect to the fixed stars. Synodic period, on the other hand, is the time it takes for the planet to return to the same apparent position in the sky as viewed from Earth. Prograde and retrograde refer to the direction of motion of a planet relative to the Sun, and geocentric refers to the belief that the Earth is the center of the universe.

Question 9

An empirical science is one that is based on:

Accepted Answer

An empirical science is one based on observed data. It relies on empirical evidence obtained through observations and experiments rather than on assumptions, computer models or mathematical calculations. While hypotheses are an important part of the scientific process, they must be tested and confirmed through empirical evidence in order to be considered scientifically valid.

Question 10

You find a moon orbiting a planet and you measure the distance between the moon and the planet once a night over the course of a few weeks. Its behavior is shown in the figure below where the time shown is the time since your first observation. What is this moon's orbital period?

Accepted Answer

The answer of You find a moon orbiting a planet...

Question 11

Figure 1
-Based on Figure 1, a superior planet at opposition:

Accepted Answer

According to Figure 1, a superior planet (which is beyond the Earth's orbit) at opposition would be on the opposite side of the sky from the Sun. Therefore, it would rise in the east at sunset and set in the west at sunrise. Choice C) is the only option that matches this description.

Question 12

Which laws are based entirely on observational data without having any theoretical framework behind them?

Accepted Answer

Empirical laws are based solely on observations without any theoretical framework. Physical laws, Galileo's laws of planetary motion, and Newton's laws of motion are all based on observations but also have a theoretical framework behind them. Deductive laws are derived from other laws through logical deduction.

Question 13

Figure 1
-Based on Figure 1, a superior planet would be seen high overhead at midnight:

Accepted Answer

According to Figure 1, the position of the superior planet at midnight changes as it orbits the sun. At opposition, the planet is directly opposite the sun in the sky, and therefore high overhead at midnight. Eastern and western quadrature refer to when the planet is at a right angle to the sun, and conjunction is when it is between the Earth and the sun. These positions do not necessarily correspond to the planet being high overhead at midnight. Therefore, the best choice is A, when the superior planet is at opposition.

Question 14

If a superior planet is observed from Earth to have a synodic period of 1.2 years, what is its sidereal period?

Accepted Answer

The answer of If a superior planet is observed from...

Question 15

Based on the figure below, an inferior planet would be farthest from the Sun and therefore most easily visible at:

Accepted Answer

The answer of Based on the figure below, an inferior...

Question 16

If the sidereal period of Jupiter is 11.9 years, what is Jupiter's synodic period as observed from Earth?

Accepted Answer

The answer of If the sidereal period of Jupiter is...

Question 17

A superior planet is one that is:

Accepted Answer

A superior planet is one that is farther from the Sun than Earth, such as Mars, Jupiter, Saturn, Uranus, and Neptune.

Question 18

When the Earth catches up to a slower moving outer planet and passes it like a faster runner overtaking a slower runner in an outside lane, the planet:

Accepted Answer

This phenomenon is known as retrograde motion, where the outer planet appears to move backward in the sky relative to the stars due to the relative positions and motions of Earth and the planet.

Question 19

The time it takes a planet to complete one full orbital revolution is commonly known as its:

Accepted Answer

The time it takes a planet to complete one full orbital revolution is commonly known as its period. Frequency refers to the number of cycles per unit of time, orbital domain is not a commonly used term in astronomy, velocity is the speed at which an object moves in a particular direction, and eccentricity refers to the degree of deviation of an object's orbit from a perfect circle.

Question 20

Astronomers argued that the heliocentric model of the Solar System was simpler than the geocentric model, based on:

Accepted Answer

The heliocentric model explained the retrograde motion of planets more simply than the geocentric model, which required complex epicycles.

Quiz 3: Motion of Astronomical Bodies

In the model of the Solar System, motion is only an apparent, not a real, motion.