How is the distance measured between earth and the next closest star outside of our solar system?
Nearest * is Proxima Centauri, at a distance of about 4.22 light years.
A triad of *s, in the northern sky, named
Proxima), is in the range (4.22 - 4.35) light year (ly) distance, from us.
A and B are bright. Yet, the less luminous Proxima is the nearest at
about 4.22 ly distance.
The quoted reference gives graphical depiction of how the
distances are measured.