Debuting along with Blue Bolt in Blue Bolt Comics #1, Sub-Zero (as he was usually referred to) was actually a Venusian astronaut!
His spaceship hit an asteroid made of frozen gases that froze the crew solid. Uncontroled, it crashed on Earth near Salt Lake City.
Somehow, the un-named Venusian survived the freezing phenomenon that killed his crewmates, but left him in an icy condition that enabled him to freeze anything he touched, or even stared at! (Ice-Vision?)
By using his atomic pistol on himself, he was able to "thaw" out for brief periods, which grew longer as the series progressed.
Realizing he was marooned, he decided to help fight evil, which had become non-existent on Venus, a planet where everyone was of the highest moral character!
Created by Bill Everett (HydroMan, Prince Namor: the Sub-Mariner, Amazing-Man, Conqueror), his first cover appearance was Blue Bolt Comics #4 (shown above) where Everett's propensity for aquatic action was put on display yet again!
Though he only appeared on the cover a couple of times, he was one of the steadiest back-up features in Blue Bolt Comics' long run.
He never got back to Venus!
But, we at Atomic Kommie Comics™ have given him a new home as part of the Lost Heroes of the Golden Age of Comics™ collection of (dare we say?) kool kollectibles including t-shirts, mugs, messenger bags, and other nifty stuff!
He's also cameoed in Alex Ross' Project SuperPowers, and hopefully, we'll be seeing a lot more of him in the future!
After all, Earth is now his home...