Comet Queen is a fictional superhero in the DC Universe. She was an ally of the Legion of Super-Heroes prior to Zero Hour.
Grava of the Earth colony Extal is a long-time fan of Star Boy, and wants desperately to become a member of the Legion. Hoping to gain superpowers she foolishly jumps from a space ship into the tail of a passing comet - failing to realize that Star Boy had flown through a particular comet while inside a starship, rather than unprotected by anything more than a futuristic space-suit. Fortunately for her this ploy works and the comet gives her the ability to fly in the vacuum of space as well as the ability to emit various "comet-like gases."
The comet tail also alters Grava's physical form, giving her hair the appearance of streaming flames; presented as nominally humanoid in flashback, her father appears to be some species derived from something akin to rats, and this would suggest she was of mixed parentage or possibly adopted.
The Story of the Vivian Girls, in What Is Known as the Realms of the Unreal.
A lot of them take drugs because they feel broken, sad, crippled, unfairly blue, can't sleep, weak-kneed, circumstances unforeseen. The Vivian Girls stay underneath. Leanne, I love your dark drawings. I nailed them to my door. Einslyn, the exclamation mark I printed on the floor. I'm singing now in a new band with Slick and Stevie Door. You knew Nazis left your keys in the canyon. You tripped, you burst, your heart's a lion. Your rainbow is not dignified. Your birthday cake is on my lap. We're singing songs. The journey's long. I won't be here before much more.