Lecture 1 Exercise 1.3

A light year a. is approximately 63,000 astronomical units b. is the time it takes for light to travel 1 astronomical unit c. is the distance that light travels in a year d. is time it takes for light to travel from the Sun to the Earth e. is the same as an astronomical unit

a. is approximately 63,000 astronomical units and c. is the distance that light travels in a year

An Astronomical Unit (A.U.) a. is the Earth - Sun Distance b. is equal to 1 solar system mass (i.e., the mass of the Solar System) c. is the distance to the nearest star to our Solar System (Proxima Centauri) d. is the same as a light-year e. is the equal to 1 solar mass (i.e, the mass of the Sun)

a. is the Earth - Sun Distance

The diameter of the Milky Way Galaxy is a. 3 million light year b. 75,000 astronomical units c. 75,000 light years d. 1 astronomical unit

c. 75,000 light years

the distance to the nearest star to our Solar System (Proxima Centauri) is approximately a. 4.2 astronomical units b. 63,000 astronomical units c. 75,000 light years d. 4.2 light years

d. 4.2 light years