Now you might be thinking, “But light is so fast! How far can it go in a year?” And you’re right! Light is incredibly fast - it can circle the Earth about seven and a half times in just one second. So, in a year, light can travel about 9.46 trillion kilometers or 5.88 trillion miles.
To understand just how far a light-year is, let’s do some size comparisons.
Sometimes, astronomers use a different unit called a parsec, which is about 3.26 light-years. But for most of us, light-years are easier to understand and imagine.
Next time you’re gazing at the stars, impress your friends with your knowledge of light-years. Just remember, it’s not a measure of time, but of distance. And it’s a way to explore the universe without even leaving your own backyard.