Proxima Centauri is not measured in miles, but in light-years. It's 4.24 light-years away from the Sun.

Here's why we use light-years:

* Vast distances: The distances between stars are so immense that using miles (or even kilometers) would result in incredibly large and unwieldy numbers.

* Light-year as a unit: A light-year is the distance light travels in one year. It's a convenient way to express these astronomical distances.

To give you a sense of scale, here's how far Proxima Centauri is in miles:

* 25 trillion miles (approximately)

That's a 25 with 12 zeros after it!