Question

Astronomers estimate that the diameter of the Andromeda galaxy is approximately 2.2 X 10^5 light-year. A light-year is the distance light travels in a vacuum in 1 year. One light-year is approximately 5.9 X 10^12 miles. What is the diameter of the Andromeda galaxy in miles? Write your answer in scientific notation.

Answer 1

Explanation:

To find the diameter of the Andromeda galaxy in miles, we can use the given information:

Diameter of Andromeda galaxy = 2.2 X 10^5 light-years

1 light-year = 5.9 X 10^12 miles

So, we can use dimensional analysis to convert light-years to miles:

2.2 X 10^5 light-years * 5.9 X 10^12 miles/light-year = 1.298 X 10^18 miles

Therefore, the diameter of the Andromeda galaxy in miles is approximately 1.298 X 10^18 miles.