Chap. 13 Astrophysics

Question 1

Define stellar clustes and constellations

Answer 1

STELLAR CLUSTER: A group of stars which are close to each other due to the collapse of a gas cloud. They are gravitationally bound, and exist in the same region of space.

CONSTELLATION: A pattern of stars in the sky as viewed from Earth. They are probably not near each other nor gravitationally bound.

Question 2

What is the **Asteroid Belt **

Answer 2

The Asteroids Belt is billions of rocky objects which orbit the Sun between the inner and outer planets.

Question 3

What are comets

Answer 3

Comets are made of ice and rock and orbit the Sun with highly eccentric orbits.

Question 4

What is a galaxy

Answer 4

A group of stars held together by gravity. Typically contains 1011 stars and is 105 ly across. Distances between stars approx. 1 ly. Distance between galaxies 106 ly. Shapes can be spiral, globular or irregular.