Today is the anniversary of the first appearance of J'onn J'onzz, also known as the Martian Manhunter, the green skinned telepathic shapeshifter who has historically been all but inseparable from DC's Justice League comics.

J'onn made his debut in Detective Comics #225, in a backup strip written by Joe Samachson and Jack Miller, and drawn by Joe Certa. In this story, Dr Erdel uses a robot-brain and teleportation to capture something from space --- as one does --- and what he captures is J'onn J'onzz. The man who brings J'onn to Earth dies not long afterwards of natural causes, and J'onn decides that he is going to use his amazing powers to help humanity --- as long as he doesn't run afoul of his one weakness, fire.

In the early Martian Manhunter stories, there are both similarities to Superman and some significant differences. Super-strength and flying are one thing --- they're synonymous with super-heroics --- but when J'onn J'onzz uses x-ray vision, super-hearing and super-breath to save lives, one has to wonder if the creators of the Martian Manhunter wouldn't be due a visit from National Comics' legal team, were they not working for the same publisher.

But it's the differences that make J'onn a compelling character. In addition to the suite of powers Superman had in the 1950s, J'onn employs shapeshifting, intangibility and psychic abilities to foil crimes --- and in his early adventures, he does it on the sly, rarely if ever turning into the familiar green Martian we all know and love. Also in contrast to Superman, he is brought to Earth as an adult, and has a comparatively limited supporting cast.

Instead of being weakened by a rock from space, he's weakened by fire, which is both more common and more synonymous with the human experience, since it's one of our first discoveries. All of these factors combine to make him seem more isolated than the more gregarious and human-passing Man of Tomorrow was portrayed as at the time, and showcase how flexible the general Superman template can be with a few well-chosen changes.

As the superhero returned to prominence, J'onn started to have more adventures in his iconic green form, becoming a founding member of the Justice League --- which is where most of his fans know him from. He remained through nearly every comics iteration, a constant and reassuring figure. Despite this, his popularity in the public eye is lacking thanks to his absence from the Superfriends cartoon --- though his turns on animated fare such as Justice League Unlimited, The Batman, and Batman: The Brave & the Bold have helped his star rise.

J'onn has had the occasional solo series --- the John Ostrander and Tom Mandrake series is a standout --- but his popularity has historically been greatest as a member of the League.

Most solo superhero comics have the hero as the body that the supporting cast orbits around --- Superman and Lois Lane, Batman and Alfred, Aquaman's Aqua-fam, and so forth. J'onn, having identities scattered all over the world, and having canonically lived so long in isolation, doesn't have a consistent supporting cast --- and he doesn't need one, because the superhero community is his supporting cast, as much as he is theirs.

Martian Manhunter and Superman showcase the different approaches to being an alien on Earth, and he and Batman demonstrate different approaches to detective work. Being around other superheroes makes both he and they stronger characters, and that's the hallmark of a true team player.