Astronomers have a special way to measure how far away stars are in space. They use something called trigonometric functions, and one important method is called parallax. Let’s break it down:

1. Parallax: As Earth goes around the Sun, it looks like nearby stars are moving a little bit compared to the faraway stars behind them. By measuring this small shift, we can figure out how far away those nearby stars really are. We use some math, called trigonometry, to do this.

2. Calculation: If the shift we measure is called the parallax angle (let's call it $p$), we can find the distance ($d$) to the star using this simple formula:

   $d = \frac{1}{p}$

This means we can measure the distance to stars that are thousands of light-years away! Pretty cool, right?