Image Comics will publish the series, which focuses on young superheroes daunted by the prospect of succeeding their parents as crimefighters.
Millar told CBR: "I think there's something sad and quite unique where these ten or 20 slightly damaged super-people feel they can never live up to their parents. And something even more tragic about the parents recognising that their children, in many ways, are their failures.
"That's the thread running in the background, and on top of all this is this massive adventure story with aliens and robots and amazing ships and vehicles and a whole world I've been building with respect to what's happening here in the real world."
Jupiter's Children features artwork from Frank Quitely, with whom Millar previously collaborated on DC Comics' The Authority.
Millar will also debut Supercrooks in March this year, followed by The Secret Service in April, and Hit Girl one month later.
Jupiter's Children launches in September.