High School

The Sun is at the center, and you see a few of the nearest stars. These stars are so distant that it is not practical to give their distances in AU. Astronomers have defined a new larger unit of distance, the light-year. One light-year (ly) is the distance that light travels in one year, roughly [tex]10^{13}[/tex] km or about 6 trillion miles. The diameter of your view in Figure 1-9 is 17 ly. The nearest star to the Sun, Proxima Centauri, is 4.2 ly away. In other words, light from Proxima Centauri takes 4.2 years to reach Earth.

Answer :

Final answer:

A light-year is the distance that light travels in one year. The nearest star to the Sun, Proxima Centauri, is 4.2 light-years away.

Explanation:

The Sun is at the center, and you see a few of the nearest stars. These stars are so distant that it is not practical to give their distances in AU. Astronomers have defined a new larger unit of distance, the light-year. One light-year (ly) is the distance that light travels in one year, roughly 1013‍km or about 6 trillion miles. The diameter of your view in Figure 1-9 is 17 ly. The nearest star to the Sun, Proxima Centauri, is 4.2 light-years away. In other words, light from Proxima Centauri takes 4.2 years to reach Earth.

Other Questions