Question

Consider a bright star in our night sky. assume its distance from earth is 68.5 light-years (ly) and its power output is 4.00 ✕ 1028 w, about 100 times that of the sun. one light-year is the distance traveled by light through a vacuum in one year.

Answer 1

A light-year measures the astronomical distance light travels in one year; it's a key concept for understanding the scale of the universe and estimating the distance to stars like the one described, which is 68.5 light-years from Earth and 100 times brighter than our Sun.

Step-by-step explanation:

The student's question relates to astrophysics and requires an understanding of light-years and the nature of power output (or luminosity) of stars compared to our Sun. A light-year is the distance light travels in one year, which is approximately 9.46 × 10¹² kilometers. As light moves at an incredible speed of 3 × 10µ kilometers per second, this measurement helps us comprehend the vast distances in the universe. Given that the star in question is 68.5 light-years away with a luminosity 100 times that of the Sun, we can appreciate its immense brightness and the considerable distance light travels before reaching Earth. This information is essential for astronomers to estimate distances and the scale of the cosmos.