If the Universe Is Teeming with Aliens ... WHERE IS EVERYBODY?: Seventy-Five Solutions to the Fermi Paradox and the Problem of Extraterrestrial Life

by Stephen Webb

In Nature, we often find that objects with a large value of some property are rare, while objects with a smaller value of that property are common. Thus bright stars of spectral class O are few in number, while dim M-class stars are widespread. Strong radio sources such as quasars are rare, while weak radio sources like stellar coronas are common.

O