Astronomy 207 Midterm 4 ~ UofC Exam
Actual Questions and Answers 2026
5) Why do asteroids and comets differ in composition?
A) Asteroids formed inside the frost line, while comets formed
outside.
B) Asteroids and comets formed at different times.
C) Comets formed from the jovian nebula, while asteroids did not.
D) Comets are much larger than asteroids.
E) Asteroids are much larger than comets. -
correct answer ✅A) Asteroids formed inside the frost line, while
comets formed outside.
Why aren't small asteroids spherical in shape?
A) The strength of gravity on small asteroids is less than the
strength of the rock.
B) Small asteroids have odd shapes because they were all chipped
off larger objects.
C) Large asteroids were once molten and therefore became
spherical, but small asteroids were never molten.
D) Large asteroids became spherical because many small collisions
chipped off pieces until only a sphere was left; this did not occur
with small asteroids. -
correct answer ✅A) The strength of gravity on small asteroids is
less than the strength of the rock.
,Astronomy 207 Midterm 4 ~ UofC Exam
Actual Questions and Answers 2026
Where are the Trojan asteroids located?
A) surrounding Jupiter
B) along Jupiter's orbit, 60° ahead of and behind Jupiter
C) in the center of the asteroid belt
D) on orbits that cross Earth's orbit
E) on orbits that cross Mars's orbit -
correct answer ✅B) along Jupiter's orbit, 60° ahead of and behind
Jupiter
How do we know that there are large gaps in the average distances
of asteroids from the Sun (within the asteroid belt)?
a) We can see the gaps through telescopes.
b)We can identify the gaps by looking for stellar occultations in
which an asteroid passed in front of a star as seen from Earth.
c) We have not actually detected any gaps, but theory says they
must exist.
d) We know the gaps must be present to explain how our
spacecraft have successfully navigated the asteroid belt without
suffering collisions.
, Astronomy 207 Midterm 4 ~ UofC Exam
Actual Questions and Answers 2026
e) We notice gaps on graphs showing the distribution of asteroids
with different orbital periods. -
correct answer ✅e) We notice gaps on graphs showing the
distribution of asteroids with different orbital periods.
The number of comets in the Oort cloud is probably about
A) a thousand.
B) a million.
C) a billion.
D) a trillion.
E) a quintillion. -
correct answer ✅D) a trillion.
Which of the following does not lend support to the idea that Pluto
is a Kuiper-belt object?
A) Pluto has a cometlike composition and density.
B) Pluto is regarded by many to be a planet.
C) Some asteroids have their own moons.
D) Pluto has a more eccentric orbit than other planets.
Actual Questions and Answers 2026
5) Why do asteroids and comets differ in composition?
A) Asteroids formed inside the frost line, while comets formed
outside.
B) Asteroids and comets formed at different times.
C) Comets formed from the jovian nebula, while asteroids did not.
D) Comets are much larger than asteroids.
E) Asteroids are much larger than comets. -
correct answer ✅A) Asteroids formed inside the frost line, while
comets formed outside.
Why aren't small asteroids spherical in shape?
A) The strength of gravity on small asteroids is less than the
strength of the rock.
B) Small asteroids have odd shapes because they were all chipped
off larger objects.
C) Large asteroids were once molten and therefore became
spherical, but small asteroids were never molten.
D) Large asteroids became spherical because many small collisions
chipped off pieces until only a sphere was left; this did not occur
with small asteroids. -
correct answer ✅A) The strength of gravity on small asteroids is
less than the strength of the rock.
,Astronomy 207 Midterm 4 ~ UofC Exam
Actual Questions and Answers 2026
Where are the Trojan asteroids located?
A) surrounding Jupiter
B) along Jupiter's orbit, 60° ahead of and behind Jupiter
C) in the center of the asteroid belt
D) on orbits that cross Earth's orbit
E) on orbits that cross Mars's orbit -
correct answer ✅B) along Jupiter's orbit, 60° ahead of and behind
Jupiter
How do we know that there are large gaps in the average distances
of asteroids from the Sun (within the asteroid belt)?
a) We can see the gaps through telescopes.
b)We can identify the gaps by looking for stellar occultations in
which an asteroid passed in front of a star as seen from Earth.
c) We have not actually detected any gaps, but theory says they
must exist.
d) We know the gaps must be present to explain how our
spacecraft have successfully navigated the asteroid belt without
suffering collisions.
, Astronomy 207 Midterm 4 ~ UofC Exam
Actual Questions and Answers 2026
e) We notice gaps on graphs showing the distribution of asteroids
with different orbital periods. -
correct answer ✅e) We notice gaps on graphs showing the
distribution of asteroids with different orbital periods.
The number of comets in the Oort cloud is probably about
A) a thousand.
B) a million.
C) a billion.
D) a trillion.
E) a quintillion. -
correct answer ✅D) a trillion.
Which of the following does not lend support to the idea that Pluto
is a Kuiper-belt object?
A) Pluto has a cometlike composition and density.
B) Pluto is regarded by many to be a planet.
C) Some asteroids have their own moons.
D) Pluto has a more eccentric orbit than other planets.
