1. Convert Light-Years to Kilometers:

* Speed of light: 299,792,458 meters per second

* Years to seconds: 1 year = 365.25 days * 24 hours/day * 60 minutes/hour * 60 seconds/minute

Calculation:

1. Distance in meters: 4.5 light-years * (299,792,458 m/s * 365.25 days/year * 24 hours/day * 60 minutes/hour * 60 seconds/minute)

2. Distance in kilometers: (Distance in meters) / 1000

Result:

Proxima Centauri is approximately 42.46 trillion kilometers from Earth.