Author Question: When a low mass star first runs short of hydrogen in its core, it becomes brighter because A) its ... (Read 102 times)

Pineappleeh · **on:** Jul 27, 2018

When a low mass star first runs short of hydrogen in its core, it becomes brighter because

A) its outer, cooler layers are shed, and we see the brighter central core.
B) it explodes as a nova.
C) the core contracts, raising the temperature and extending the hydrogen burning shell outward.
D) the helium flash increases the size of the star immensely.
E) helium fusion gives off more energy than does hydrogen.

Question 2

On average, active galaxies are rare and most are fairly distant from us.

Indicate whether the statement is true or false