How far does light travel in one year?

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Dive into the AST2002 Astronomy Midterm at UCF. Enhance your understanding through engaging flashcards and insightful multiple-choice questions. Prepare effectively and boost your confidence for this academic challenge!

Light travels incredibly fast, at a speed of about 299,792 kilometers per second, or roughly 186,282 miles per second. To determine how far light travels in one year, we can calculate the distance by using this speed.

First, we find how many seconds there are in a year:

A year has approximately 365.25 days (accounting for leap years),
Each day has 24 hours,
Each hour has 60 minutes,
Each minute has 60 seconds.

This leads to: 365.25 days/year × 24 hours/day × 60 minutes/hour × 60 seconds/minute = about 31,557,600 seconds/year.

Next, multiplying this number by the speed of light: 31,557,600 seconds/year × 186,282 miles/second gives approximately 5.879 trillion miles.

Hence, the correct choice reflects this precise calculation, making it the accurate distance that light travels in one year. This value is significant in astronomy because it defines the unit known as a light-year, which is frequently used to measure astronomical distances.