Question

1. choose the best answer.

each galilean moon is ____, meaning that one side of the moon always faces the planet.

tidally locked
placid
rotationally challenged
sealed

1. choose the best answer.

why is ganymede considered a moon and not a planet?
it is a satellite orbiting jupiter and not the sun.
it is smaller than any dwarf planet.
it is more like an asteroid than a planet.
it does not have a magnetic field.

Explanation:

Question 5

To solve this, we analyze the term for a moon where one side always faces the planet. "Tidally locked" is the scientific term for this phenomenon, as tidal forces cause the moon's rotation period to match its orbital period around the planet. The other options ("placid", "rotationally challenged", "sealed") do not relate to this astronomical concept.

Ganymede is a moon (satellite) of Jupiter. By definition, a moon is a natural satellite orbiting a planet, while a planet orbits the sun. So Ganymede is considered a moon (not a planet) because it orbits Jupiter (a planet) and not the sun. The other options: being smaller than a dwarf planet, being more like an asteroid, or not having a magnetic field are incorrect reasons (Ganymede does have a magnetic field, and size/asteroid - like appearance are not the defining factors for moon vs planet classification).

Answer:

The option "tidally locked" (the first option among the four choices for question 5, with the text "tidally locked").

Question 6