Asteroids & Comets
1) a) What are the two principal components in the compositions of asteroids? _________ and _________
b) What are the two principal components in the compositions of comets? _________ and _________
2) List at least five differences between asteroids and comets
3) a) Are asteroids generally found inside the ice line or outside?
b) Are comets generally found inside the ice line or outside?
4) Where in the Solar System do we find asteroids?
a) Main Belt
b) 60° in front of Jupiter and 60° behind Jupiter
c) Near the ecliptic plane
d) Crossing planetary orbits
e) Captured into orbits about some planets as irregular moons
f) Asteroids are found in all of the above locations
5) a) What is the primary source of short-period comets?
b) What is the primary source of long-period comets?
6) True/False
a) Since they are composed of rock and metal, asteroids are always solid intact objects.
b) Cometary nuclei always light up when they pass into the inner solar system.
Critical Thinking Questions
1) Why did comets get the nickname "dirty snowballs?"
2) Why are comets so active when they pass into the inner solar system? Why do asteroids never put on a show like comets?
3) Based upon what you know about asteroid and comet orbits, which are more likely to pose an impact threat to Earth?
4) Why are most asteroids not round? If they are composed of rock and metal, why do so many of them have such low densities?
5) Is it likely that the asteroid belt formed when a planet exploded? What evidence exists to either support or counter this hypothesis?
6) Explain why a comet's tail does not always trail the comet in its orbit.
Meteoroids, Meteors, & Meteorites
1) What is the difference between a meteoroid, a meteor, and a meteorite?
2) Where is the best place to go hunting for meteorites on Earth? Explain your answer.
Dwarf Planets
Important Facts
1) a) Which asteroid was recently upgraded to dwarf planet? _____________
b) List at least three Kuiper Belt objects were recently upgraded to dwarf planet status.
_____________, _____________, and _____________
2) What are the three criteria that the International Astronomical Union requires objects to meet in order to classify them as planets?
Critical Thinking Questions-
1) Why do many planetary scientists disagree with the classification of Pluto (or Ceres, Charon, and Eris) as a planet? List several reasons.
2) How does Ceres compare in size and mass to the rest of the asteroid belt?
3) Spectroscopic observations of Ceres suggest that water may have been incorporated into some asteroids. What would the presence of "wet" asteroids tell us about the location of the ice line?
4) Jack claims that Pluto has three moons: Charon, Nix, and Hydra. Jill disagrees with Jack's claim, insisting that Nix and Hydra are moons of both Pluto and Charon. Who is correct, and why is that person correct?