It takes 3x107 years for a particular star to make one orbit around its galaxy. Assume that this star's orbit in its galaxy is circular with a diameter of 104 light years. A light year is the distance that light travels in one year. There are about 5.859x10¹² miles in 1 light-year. Estimate how many miles this star travels in one year.
The star travels about _____ miles in one year.
Number of years required
Distance travelled
3 x 107 years
Star's orbit = circumference =
= π x 104 light years
= π x 104 x 5.859 x 1012 miles
= 5.859 π x 1016 miles
1 year
x