The temperature began to rise at the center of the solar nebula because
A) the nebula was contracting and that fast-moving material collided and increased the thermal energy.
B) supernova explosions were stirring up the material there and causing turbulence.
C) fusion reactions were beginning in the core,releasing tremendous amounts of heat.
D) massive stars nearby were heating the nebula with their ultraviolet radiation.

Question

Quizplus · Accepted Answer

The temperature began to rise due to the process of gravitational contraction, which caused the material in the center of the nebula to collide and increase thermal energy. This is known as the nebular hypothesis, which is the most widely accepted explanation for the formation of our solar system.

The Temperature Began to Rise at the Center of the Solar