Question 1

Why were Adams and Le Verrier acknowledged as the discoverers of the planet Neptune?

Accepted Answer

Adams and Le Verrier predicted the position of Neptune based on discrepancies in the orbit of Uranus. While they did not physically observe the planet through a telescope, their calculations led to its discovery.

Question 2

Which planet receives the least amount of energy from the Sun?

Accepted Answer

Neptune receives the least amount of energy from the Sun because it is the farthest planet from the Sun, with an average distance of about 2.8 billion miles (4.5 billion kilometers) away. This means that it receives only about 1/900th the amount of sunlight that Earth does.

Question 3

When charged particles oscillate around magnetic field lines of a planet, they emit radiation in the microwave region of the spectrum.

Accepted Answer

Charged particles oscillating around magnetic field lines typically emit radiation in the radio frequency range, not the microwave region. This is known as synchrotron radiation.

Question 4

Jupiter radiates more energy than it receives from the Sun, mostly because it is still contracting under its own gravity.

Accepted Answer

Jupiter is still contracting, which produces heat energy through gravitational compression. This results in Jupiter radiating more energy than it receives from the Sun.

Question 5

Jupiter and Saturn are composed primarily of:

Accepted Answer

The answer of Jupiter and Saturn are composed primarily of:
...

Question 6

Assume you want to deduce the radius of a planet in our Solar System as it occults a background star when the relative velocity between the planet and the Earth is 30 km/s. If the star crosses through the middle of the planet and disappears for a total of 26 minutes, what is the planet's radius?

Accepted Answer

The answer of Assume you want to deduce the radius...

Question 7

Jupiter's strong aurorae result from particles ejected by Io's volcanoes.

Accepted Answer

Jupiter's strong aurorae result from high-energy particles ejected by Io's volcanoes, which get caught in Jupiter's magnetic field and interact with its atmosphere.

Question 8

Jupiter is approximately 20 times more massive than the Earth.

Accepted Answer

Jupiter is approximately 318 times more massive than Earth, not 20 times.

Question 9

Jupiter's mass is more than twice the mass of all the other planets in our Solar System combined.

Accepted Answer

Jupiter's mass is 1.898 x 10^27 kg, while the combined mass of all the other seven planets is only 5.972 x 10^24 kg, which is less than one-third of Jupiter's mass. Therefore, Jupiter's mass is more than twice the mass of all the other planets combined.

Question 10

Which of the giant planets was discovered by accident by William Herschel?

Accepted Answer

Uranus was discovered by accident by William Herschel in 1781, while he was surveying the stars with a telescope.

Question 11

The giant planets are made primarily of water and carbon dioxide.

Accepted Answer

The giant planets, also known as gas giants, are primarily composed of hydrogen and helium, with smaller amounts of other elements such as methane, ammonia, and water. While these planets may contain small amounts of carbon dioxide, it is not a major component of their composition.

Question 12

Which of the giant planets was predicted to exist mathematically before it was ever seen through a telescope?

Accepted Answer

Neptune was predicted to exist mathematically before it was observed through a telescope. The irregularities in Uranus' orbit prompted astronomers to hypothesize the presence of another planet, which was later confirmed with Neptune's discovery.

Question 13

On the giant planets, the atmospheric vortices that occur almost always lie between oppositely directed zonal winds.

Accepted Answer

This statement is true. Vortices on the giant planets, such as Jupiter and Saturn, are found in between zones of opposing winds. These vortices can appear as oval-shaped storms, such as Jupiter's famous Great Red Spot. This pattern of winds and vortices is driven by the planet's internal heat and rotation, and creates complex weather patterns unique to each planet.

Question 14

What is the angular diameter of Neptune if its diameter is 50,000 km and its distance is 30 AU?

Accepted Answer

The angular diameter can be calculated using the formula: angular diameter = (diameter / distance) * (206265), where the distance is in the same units as the diameter. Converting 30 AU to kilometers (1 AU = 149,597,870.7 km), the angular diameter is approximately 2 arcseconds.

Question 15

All the giant planets, not just Jupiter, have atmospheric bands and storms.

Accepted Answer

This statement is true, as all the giant planets in our solar system have visible atmospheric bands and storms. Uranus and Neptune also have dark spots similar to Jupiter's Great Red Spot.

Question 16

Which of these observations would allow you to measure the mass of a planet?

Accepted Answer

By observing the orbit of one of the planet's moons, we can determine the planet's mass using Kepler's laws of planetary motion. The mass of the planet affects the moon's orbit, which allows us to calculate the planet's mass. The other choices are not directly related to measuring a planet's mass.

Question 17

The compositions of Uranus and Neptune differ primarily from that of Jupiter and Saturn in that the outer two planets contain more:

Accepted Answer

The compositions of Uranus and Neptune differ primarily from that of Jupiter and Saturn in that they contain more water. Uranus and Neptune are often called ice giants due to their high concentration of water, ammonia, and methane in their atmospheres and interiors. In contrast, Jupiter and Saturn are considered gas giants because they are primarily composed of hydrogen and helium gases.

Question 18

The different cloud layers seen in Jupiter's bands represent clouds at different altitudes in Jupiter's atmosphere.

Accepted Answer

The different cloud layers seen in Jupiter's bands are formed by clouds at different altitudes in Jupiter's atmosphere. The white ammonia clouds sit at higher altitudes, while the darker colored clouds are at lower altitudes.

Question 19

Uranus and Neptune are less massive than Jupiter and Saturn, probably because they formed earlier than Jupiter or Saturn.

Accepted Answer

Uranus and Neptune are less massive than Jupiter and Saturn because they are located farther from the Sun, where there is less gas and dust to form planets. Additionally, Jupiter and Saturn are believed to have undergone a process called runaway gas accretion, where they rapidly gathered large amounts of gas from the protoplanetary disk, while Uranus and Neptune did not have enough time to undergo this process.

Question 20

You observe Neptune as it occults a background star when the relative velocity between Neptune and the Earth is 30 km/s, and the star crosses through the middle of the planet and disappears for 27.6 minutes. What is Neptune's diameter?

Accepted Answer

Neptune's diameter is given by:$$D = v 	imes t$$where:* D is the diameter* v is the relative velocity* t is the time it takes for the star to cross the planetPlugging in the given values, we get:$$D = 30 	ext{ km/s} 	imes 27.6 	ext{ minutes} 	imes 60 	ext{ s/minute} = 4.9 	imes 10^4 	ext{ km}$$Which is closest to choice A.

Quiz 10: Worlds of Gas and Liquid the Giant Planets