User blog comment:YoungJusticeFan/YoungJusticeFan's Blog Post/@comment-3462923-20110609013619/@comment-3465526-20110609115043

She's an alien. Her human persona is based on a bad old sitcom named "Hello Megan" about a teenaged girl named Megan who has a catchphrase of "Hello! Megan" -- there's a promo for it on the "Comedy Classic Network" in "Downtime" where Artemis is sitting in front of the TV ignoring it and one scene from the show (with laugh track) appears as Miss Martian's memory during the Superboy memory restoration in "Bereft" -- it's also, presumably, the "episode 14" show in which "Granny Jones" has a cookie recipe in "episode 14 of ... never mind" the first time Megan burns cookies. She uses the catchphrase because she IS a bad teenage girl stereotype from a bad 80's(?) sitcom -- its how she's trying to be human when she doesn't really understand human.