__________are the large oval grooves found on Uranus's moon Miranda that indicate past geologic ...

__________are the large oval grooves found on Uranus's moon Miranda that indicate past geologic activity.
 
  A) Ovoids
  B) Ovoli
  C) Ovines
  D) Ovules

Question 2

Which of the following planets was reclassified as a dwarf planet by the International Astronomical Union (IAU) in 2006?
 
  A) Pluto
  B) Earth
  C) Uranus
  D) Saturn

Question 3

The Jovian planets have low density because:
 
  A) they formed in the outer solar nebula where water vapor could freeze to form ice particles.
  B) interactions between their magnetic fields and the solar wind generate powerful electric currents.
  C) the continuous blast of micrometeorites evaporates surface ice, leaving behind embedded minerals.
  D) the heat flowing out of them emits about twice as much less energy as they absorb from the Sun.

Question 4

The Roche limit is the:
 
  A) distance from the Sun within which a planet cannot retain or create an atmosphere.
  B) minimum distance between a planet and a satellite that can hold itself together by its own gravity.
  C) minimum mass required by an object in the Solar System to be classified as a planet instead of a star.
  D) distance from Earth at which radio communication with a satellite is lost.