Author Question: What do we mean by the period of heavy bombardment in the context of the history of our solar ... (Read 145 times)

plus1 · **on:** Jul 27, 2018

What do we mean by the period of heavy bombardment in the context of the history of our solar system?

A) the first few hundred million years after the planets formed, which is when most impact craters were formed
B) the time before planetesimals finished accreting into planets, during which many growing planetesimals must have shattered in collisions
C) the time during which heavy elements condensed into rock and metal in the solar nebula
D) the period about 65 million years ago when an impact is thought to have led to the extinction of the dinosaurs

Question 2

How much brighter is a Sun-like star than the reflected light from a planet orbiting around it?

A) a hundred times brighter
B) a thousand times brighter
C) ten thousand times brighter
D) a million times brighter
E) a billion times brighter