What is one possible reasons Jupiter and Saturn radiate more energy than they receive from the Sun?
a. Magnetic and electric fields heat the planet.
b. Fusion reactions of hydrogen into helium inside the planet provide an additional heat source.
c. The planets are still radiating heat from when they first formed.
d. Friction between the planet and its moons heat the planet.
Question 2
Why is Saturn's moon Titan able to retain an atmosphere?
a. Titan only contains light gases which are easy to retain.
b. Titan has a large enough mass and is cold enough.
c. Titan is biologically active.
d. It is so close to Saturn that Saturn's gravity retains Titan's atmosphere.