Find out what is the closest star to Earth.
The closest known star to Earth is Proxima Centauri, which is 4.24 light-years away. It is part of the Alpha Centauri star system, and is also known as Alpha Centauri C.
Complete the following task based on the instruction and optional input provided.### Instruction:
Find out what is the closest star to Earth.

### Output:
The closest known star to Earth is Proxima Centauri, which is 4.24 light-years away. It is part of the Alpha Centauri star system, and is also known as Alpha Centauri C.