Question 1

What major contribution did the German mathematician Karl Friedrich Gauss make to astronomy?

Accepted Answer

A) He discovered a regular progression of planetary distances from the Sun, so that each planet's orbit could be calculated knowing the distance of any one planet from the Sun. 
B) He developed a method for computing an object's temperature from measurements of the intensity of emitted light at only two wavelengths. 
C) He derived the Stefan-Boltzmann law, emitted flux = $\sigma$ T4, mathematically, from basic physical principles. 
D) He developed a method for computing an object's orbit from only three observations. 
A) He discovered a regular progression of planetary distances from the Sun, so that each planet's orbit could be calculated knowing the distance of any one planet from the Sun. 
B) He developed a method for computing an object's temperature from measurements of the intensity of emitted light at only two wavelengths. 
C) He derived the Stefan-Boltzmann law, emitted flux = $\sigma$ T4, mathematically, from basic physical principles. 
D) He developed a method for computing an object's orbit from only three observations.

Question 2

Which of the following biochemical materials has been found and identified in rocks recovered from outer space (e.g., meteorites)?

Accepted Answer

A) viruses 
B) living cells 
C) lichens and mosses 
D) amino acids 
A) viruses 
B) living cells 
C) lichens and mosses 
D) amino acids

Question 3

A technique that is proving very useful for determining the shapes of a large number of asteroids is:

Accepted Answer

A) radar signals reflected from the asteroid's surface. 
B) direct photography from spacecraft. 
C) optical and infrared Doppler shift measurements as the asteroid rotates. 
D) CCD photography using large, Earth-based telescopes. 
A) radar signals reflected from the asteroid's surface. 
B) direct photography from spacecraft. 
C) optical and infrared Doppler shift measurements as the asteroid rotates. 
D) CCD photography using large, Earth-based telescopes.

Question 4

Which one of the following does NOT have Lagrange points?

Accepted Answer

A) the Sun 
B) Earth 
C) Jupiter 
D) Neptune 
A) the Sun 
B) Earth 
C) Jupiter 
D) Neptune

Question 5

Why do we think that about 6% of the meteorites landing on Earth originate from Vespa?

Accepted Answer

A) Their trajectories match the orbit of Vespa. 
B) The ages of the meteorites match the age of the asteroid. 
C) The chemical composition of the asteroids matches the chemical composition of a large crater on Vespa where the Dawn spacecraft obtained infrared spectra. 
D) The meteors are all about the same size, indicating that they came from the same impact crater on Vespa. 
A) Their trajectories match the orbit of Vespa. 
B) The ages of the meteorites match the age of the asteroid. 
C) The chemical composition of the asteroids matches the chemical composition of a large crater on Vespa where the Dawn spacecraft obtained infrared spectra. 
D) The meteors are all about the same size, indicating that they came from the same impact crater on Vespa.

Question 6

The combined matter in the asteroid belt would produce an object of what approximate size?

Accepted Answer

A) about 1500 km in diameter-significantly smaller than the Moon 
B) about the size of Earth 
C) only a few kilometers in diameter-similar to an average mountain on Earth 
D) about the size of Mercury 
A) about 1500 km in diameter-significantly smaller than the Moon 
B) about the size of Earth 
C) only a few kilometers in diameter-similar to an average mountain on Earth 
D) about the size of Mercury

Question 7

How well does Ceres fit the Titus-Bode rule?

Accepted Answer

A) Neither the Ceres/Mars ratio nor the Jupiter/Ceres ratio falls into the range suggested by the Titus-Bode rule. 
B) The Ceres/Mars ratio fits the Titus-Bode rule but the Jupiter/Ceres ratio does not. 
C) The Ceres/Mars ratio does not fit the Titus-Bode rule but the Jupiter/Ceres ratio does. 
D) Both the Ceres/Mars ratio and the Jupiter/Ceres ratio fall into the range suggested by the Titus-Bode rule. 
A) Neither the Ceres/Mars ratio nor the Jupiter/Ceres ratio falls into the range suggested by the Titus-Bode rule. 
B) The Ceres/Mars ratio fits the Titus-Bode rule but the Jupiter/Ceres ratio does not. 
C) The Ceres/Mars ratio does not fit the Titus-Bode rule but the Jupiter/Ceres ratio does. 
D) Both the Ceres/Mars ratio and the Jupiter/Ceres ratio fall into the range suggested by the Titus-Bode rule.

Question 8

The asteroid Mathilde has a mean density of only 1300 kg/m3, which is about half the density of rock. What is believed to be the reason for Mathilde's low density?

Accepted Answer

A) Mathilde is a "rubble pile," having been shattered by collisions with other asteroids. 
B) Mathilde is a binary asteroid that is too far away for us to see the individual components; the low density is an illusion created by the space between the two rocky components. 
C) Mathilde is composed of about 1/4 rock and 3/4 ice. 
D) Mathilde is a primitive asteroid, composed of loosely aggregated dust grains from the early solar nebula. 
A) Mathilde is a "rubble pile," having been shattered by collisions with other asteroids. 
B) Mathilde is a binary asteroid that is too far away for us to see the individual components; the low density is an illusion created by the space between the two rocky components. 
C) Mathilde is composed of about 1/4 rock and 3/4 ice. 
D) Mathilde is a primitive asteroid, composed of loosely aggregated dust grains from the early solar nebula.

Question 9

The Titus-Bode Law is derived from:

Accepted Answer

A) Newton's laws of motion. 
B) the conservation of energy and angular momentum. 
C) Kepler's third law. 
D) None of the above is correct. The Titus-Bode "law" is more of a coincidence than a fundamental law of nature. 
A) Newton's laws of motion. 
B) the conservation of energy and angular momentum. 
C) Kepler's third law. 
D) None of the above is correct. The Titus-Bode "law" is more of a coincidence than a fundamental law of nature.

Question 10

What evidence do we have from meteorite studies that suggest that the formation of our Sun and solar system might have been triggered by a supernova explosion?

Accepted Answer

A) the detection of pure iron in many meteorites 
B) the measurement of a fusion crust around most meteorites, indicating intense heating at some time 
C) the discovery of amino acids in some meteorites 
D) the discovery of the decay products of short-lived radioactive elements within some meteorites 
A) the detection of pure iron in many meteorites 
B) the measurement of a fusion crust around most meteorites, indicating intense heating at some time 
C) the discovery of amino acids in some meteorites 
D) the discovery of the decay products of short-lived radioactive elements within some meteorites

Question 11

The asteroid belt extends from 2 to 3.5 au from the Sun. If we take the average radius to be 2.75 au, what is the average sidereal period?

Accepted Answer

A) 1.99 years 
B) 2.8 years 
C) 4.56 years 
D) 46.8 years 
A) 1.99 years 
B) 2.8 years 
C) 4.56 years 
D) 46.8 years

Question 12

The fact that there are several distinct and different types of meteorites (stony, stony iron, and iron) is probably indicative of:

Accepted Answer

A) preferential accretion of iron particles to other iron particles because of their magnetic properties, leaving stony particles to accrete separately. 
B) fragmentation of asteroids that had become differentiated in a similar fashion to Earth (with the heavier iron sinking to the center). 
C) different amounts of heating and "erosion" of the outer layers of meteorites as they pass through Earth's atmosphere. 
D) formation in different parts of the early solar nebula, with stones condensing closer to the Sun and irons farther out. 
A) preferential accretion of iron particles to other iron particles because of their magnetic properties, leaving stony particles to accrete separately. 
B) fragmentation of asteroids that had become differentiated in a similar fashion to Earth (with the heavier iron sinking to the center). 
C) different amounts of heating and "erosion" of the outer layers of meteorites as they pass through Earth's atmosphere. 
D) formation in different parts of the early solar nebula, with stones condensing closer to the Sun and irons farther out.

Question 13

How big is the largest asteroid, Ceres, in comparison with the largest mare or impact basin on the Moon, Mare Imbrium?

Accepted Answer

A) Ceres is much larger than Mare Imbrium. 
B) Ceres is much smaller, because asteroids are very small objects (1 km diameter), whereas maria are large (100-1000 km diameter). 
C) The Mare Imbrium is much larger than Ceres. 
D) Their size is very similar-about 1000 km across. 
A) Ceres is much larger than Mare Imbrium. 
B) Ceres is much smaller, because asteroids are very small objects (1 km diameter), whereas maria are large (100-1000 km diameter). 
C) The Mare Imbrium is much larger than Ceres. 
D) Their size is very similar-about 1000 km across.

Question 14

The asteroid Vesta is rounded and shows signs of differentiation, even though it is only 525 km in diameter. What is believed to be the reason for this?

Accepted Answer

A) Vesta is unusually dense, so that, despite its small size, it has pulled itself gravitationally into a sphere. 
B) Vesta was heated by a massive collision. 
C) Vesta was heated by radioactivity soon after its formation. 
D) Vesta was initially formed hot in the solar nebula and has managed to avoid large collisions ever since. 
A) Vesta is unusually dense, so that, despite its small size, it has pulled itself gravitationally into a sphere. 
B) Vesta was heated by a massive collision. 
C) Vesta was heated by radioactivity soon after its formation. 
D) Vesta was initially formed hot in the solar nebula and has managed to avoid large collisions ever since.

Question 15

We have studied asteroids by all of the following methods EXCEPT ONE. Which is the EXCEPTION?

Accepted Answer

A) sending radar pulses to reflect off the surface and analyzing the result 
B) watching the variations in the sunlight reflecting off the asteroids 
C) sending a spacecraft to orbit an asteroid 
D) landing a robotic rover to survey an asteroid 
A) sending radar pulses to reflect off the surface and analyzing the result 
B) watching the variations in the sunlight reflecting off the asteroids 
C) sending a spacecraft to orbit an asteroid 
D) landing a robotic rover to survey an asteroid

Question 16

The half-life for the decay of 26Al into 26Mg is 720,000 years. Suppose a meteorite was formed 4.6 billion years ago that contained 26Al. How much 26Al does it contain now?

Accepted Answer

A) almost all of its original amount 
B) half of its original amount 
C) 1/6389 of its original amount 
D) almost none 
A) almost all of its original amount 
B) half of its original amount 
C) 1/6389 of its original amount 
D) almost none

Question 17

The nearest star beyond the Sun is Proxima Centauri, which is approximately 4.22 ly away. Suppose Proxima Centauri is surrounded by an Oort cloud the same size as our own. What would be the distance between these Oort clouds as a fraction of the distance between these two stars?

Accepted Answer

A) 0.27 
B) 0.63 
C) 0.87 
D) 0.99 
A) 0.27 
B) 0.63 
C) 0.87 
D) 0.99

Question 18

The impact of a 10-km-diameter asteroid on the surface of Earth would very likely:

Accepted Answer

A) shatter Earth into fragments. 
B) create havoc near the impact site but have relatively little lasting effect elsewhere. 
C) shatter the global ecology and cause the extinction of a large percentage of all species living on Earth. 
D) completely destroy all life on Earth. 
A) shatter Earth into fragments. 
B) create havoc near the impact site but have relatively little lasting effect elsewhere. 
C) shatter the global ecology and cause the extinction of a large percentage of all species living on Earth. 
D) completely destroy all life on Earth.

Question 19

A typical comet loses what fraction of its mass each time it passes close to the Sun (i.e., at each perihelion passage)?

Accepted Answer

A) less than 0.001% 
B) 10% 
C) 0.1% 
D) 0.5% to 1% 
A) less than 0.001% 
B) 10% 
C) 0.1% 
D) 0.5% to 1%

Question 20

Asteroids that orbit the Sun at the same distance as Jupiter are known as the:

Accepted Answer

A) Adenoids. 
B) Apollo asteroids. 
C) Trojan asteroids. 
D) Jupitoids. 
A) Adenoids. 
B) Apollo asteroids. 
C) Trojan asteroids. 
D) Jupitoids.

Exam 15: Asteroids, Comets, and Impacts

What major contribution did the German mathematician Karl Friedrich Gauss make to astronomy?

Which of the following biochemical materials has been found and identified in rocks recovered from outer space (e.g., meteorites)?

A technique that is proving very useful for determining the shapes of a large number of asteroids is:

Which one of the following does NOT have Lagrange points?

Why do we think that about 6% of the meteorites landing on Earth originate from Vespa?

The combined matter in the asteroid belt would produce an object of what approximate size?

How well does Ceres fit the Titus-Bode rule?

The asteroid Mathilde has a mean density of only 1300 kg/m3, which is about half the density of rock. What is believed to be the reason for Mathilde's low density?

The Titus-Bode Law is derived from:

What evidence do we have from meteorite studies that suggest that the formation of our Sun and solar system might have been triggered by a supernova explosion?

The asteroid belt extends from 2 to 3.5 au from the Sun. If we take the average radius to be 2.75 au, what is the average sidereal period?

The fact that there are several distinct and different types of meteorites (stony, stony iron, and iron) is probably indicative of:

How big is the largest asteroid, Ceres, in comparison with the largest mare or impact basin on the Moon, Mare Imbrium?

The asteroid Vesta is rounded and shows signs of differentiation, even though it is only 525 km in diameter. What is believed to be the reason for this?

We have studied asteroids by all of the following methods EXCEPT ONE. Which is the EXCEPTION?

The half-life for the decay of 26Al into 26Mg is 720,000 years. Suppose a meteorite was formed 4.6 billion years ago that contained 26Al. How much 26Al does it contain now?

The nearest star beyond the Sun is Proxima Centauri, which is approximately 4.22 ly away. Suppose Proxima Centauri is surrounded by an Oort cloud the same size as our own. What would be the distance between these Oort clouds as a fraction of the distance between these two stars?

The impact of a 10-km-diameter asteroid on the surface of Earth would very likely:

A typical comet loses what fraction of its mass each time it passes close to the Sun (i.e., at each perihelion passage)?

Asteroids that orbit the Sun at the same distance as Jupiter are known as the:

Astronomy and the Universe

Knowing the Heavens

Eclipses and the Motion of the Moon

Gravitation and the Waltz of the Planets

The Nature of Light

Optics and Telescopes

Comparative Planetology I: Our Solar System

Comparative Planetology II: the Origin of Our Solar System

The Living Earth

Our Barren Moon

Mercury, Venus, and Mars: Terrestrial, yet Unique

Jupiter and Saturn: Lords of the Planets

Jupiter and Saturns Satellites of Fire and Ice

Uranus, Neptune, Pluto, and the Kuiper Belt: Remote Worlds

Our Star, the Sun

The Nature of the Stars

The Birth of Stars

Stellar Evolution: on and After the Main Sequence

Stellar Evolution: The Death of Stars

Stellar Remnants: Neutron Stars and Black Holes

Our Galaxy

Galaxies

Quasars and Active Galaxies

Cosmology: The Origin and Evolution of the Universe

Exploring the Early Universe

The Search for Extraterrestrial Life

Filters

The asteroid Mathilde has a mean density of only 1300 kg/m³, which is about half the density of rock. What is believed to be the reason for Mathilde's low density?

The half-life for the decay of ²⁶Al into ²⁶Mg is 720,000 years. Suppose a meteorite was formed 4.6 billion years ago that contained ²⁶Al. How much ²⁶Al does it contain now?