Author Question: In composition, mass, and density, Jupiter is most like: A) a huge comet. B) a gigantic ... (Read 138 times)

pepyto · **on:** Jul 27, 2018

In composition, mass, and density, Jupiter is most like:

A) a huge comet.
B) a gigantic asteroid.
C) the Sun.
D) a huge Kuiper belt Object.
E) a large terrestrial planet.

Question 2

Why do we think Mercury contracted within about a billion years after it formed?

What will be an ideal response?

Melissahxx · **Reply #1 on:** Jul 27, 2018

Answer to Question 1

C

Answer to Question 2

The surface of Mercury is marked by long, high cliffs. Such features result from tectonic compression, but there are no corresponding features due to tectonic stretching. This suggests the whole planet contracted as it rapidly cooled in its early history. We can date the contraction from the age of the volcanic flows on its surface: volcanic (and all geologic) activity probably came to an abrupt halt as a result of the planet's contraction.