Okay, maybe not. But someone at the space agency is a comic-book nerd -- go figure! -- the stunning image of the day on the NASA website is accompanied by the headline "A Green Ring Fit for a Superhero." It's a shot from the Spitzer Space Telescope of a glowing emerald nebula "reminiscent of the glowing ring wielded by the superhero Green Lantern." The description goes on to name check the Guardians of Oa, power rings and the Green Lantern Corps. Visit the NASA website to enjoy the image at full size.