Exam 24: Stars, Space, and Galaxies

A(n) ____________________ is a distance equal to 3.26 light-years.

The carbon in our bodies was created during the big bang.

Which list correctly orders the layers of the Sun from the center outward?

In the ____ model, the gravitational force of the Universe is not sufficient to stop the current expansion and the galaxies will continue to fly apart forever.

Define apparent brightness and absolute brightness.

What is first-generation energy?

A cloud of interstellar gas and dust is called a ____.

The Sun is composed primarily of hydrogen and ____________________.

A ____ is a large volume of space containing many billions of stars held together by their mutual gravitational attraction.

How big is the Sun's core and how much hydrogen fuel does it have left?

Within a star, gravity pulls particles inward, but at the same time, ____________________ energy drives them outward.

The process of absorption, emission, and convection slows down photons traveling from the Sun's core so much that it takes about one million years to reach the photosphere.

Describe sunspots.

____________________ are comparatively cool, dark regions on the Sun's surface caused by magnetic disturbances.

The ____________________ brightness of a star decreases the farther you are from it.

What do astrophysicists call the poorly understood repulsive force that causes the expansion of the Universe to accelerate?

Describe a red giant.

Describe the radiative and convective zones.

Hubble's law states that the ____.

The expansion of the Universe provides a piece of evidence in support of the big bang theory.