After all that deeper thinking about character motivation, it’s time for something light-hearted and fun: a new Legionnaire is introduced in Adventure Comics #282 (Jan 1961): Star Boy!
Lana wants to make Superboy jealous, so she eavesdrops as a new teen superhero arrives from the future to meet Superboy. She learns the teen’s identity is Thom Kallor from the planet Xanthu. Sure, that’ll do. He was caught in the tail of a comet and it gave him invulnerability, super-strength, super-cooling-breath, infra-red vision, x-ray vision, and electrical vision and subsequently jjoined the 30th century Legion of Super-Heroes. He also can fly, but they have have not established that all Legionnaires can fly with flight rings yet.
Star Boy needs Superboy’s help to catch some criminals in the future, since his x-ray vision can’t see through copper. Why not? Of course Lana’s plan backfires and the two heroes team up to make her even more jealous. Not petty at all.
It’s interesting that the writers could have not made this a Legion story – there have been plenty of super-powered teen beings that come to Earth to interact with Superboy – and the Legion only appear in a single panel – but I guess this is the start of the deepening of the Legion mythos and world-building.