Question

The brightest star in the night sky in the northern hemisphere is Sirius. Its distance from Earth is estimated to be 8.7 light years. A light year is the distance light travels in one year. Light travels at a speed of 3.00 × 108 m/s. Calculate the distance from Earth to Sirius in miles. (1 mi = 5280 ft) g

Answer 1

Answer:$5.11(10)^{13}miles$

Explanation:

A light year is a unit of length and is defined as "the distance a photon would travel in vacuum during a Julian year at the speed of light at an infinite distance from any gravitational field or magnetic field. "

In other words: It is the distance that the light travels in a year.  

This unit is equivalent to $5.879(10)^{12}miles$, which mathematically is expressed as:

$1Ly=5.879(10)^{12}miles$

Doing the conversion:

$8,7Ly.\frac{5.879(10)^{12}miles}{1Ly}=5.11(10)^{13}miles$  This is the distance from Earth to Sirius in miles.