Flying whales, walking trees, three-eyed killer birds – NASA and SETI imagine life on other worlds.

On Aurelia, an Earth-sized planet half shrouded in
perpetual darkness, vast floodplains give way to groves of treelike
stinger fans that use ambulatory roots to creep across the muddy
surface. On Blue Moon, a lunar orb in an adjacent solar system
light-years from Aurelia, winged skywhales gulp aerial plankton
suspended in the dense atmosphere, while balloon plants float beneath
the canopies of massive pagoda tree forests, buoyed by hydrogen
gas-filled membranes like miniature Hindenburgs.

Sounds like a pair of scenes ripped from your standard off-world
fantasy novel, except the science behind these alien planets isn’t
fiction. Aurelia and Blue Moon are based on computer models created by
NASA and SETI Project researchers to help identify which stars among
the universe’s 70 sextillion are most likely to support life. CGI
representations of the worlds first appeared in a National Geographic
documentary; the film and related interactive simulations are on
display through February at the London Science Museum. A US tour is
planned for this fall.

Scientists began with the essential ingredient for life: They
assumed both worlds in the exhibit contained water. They then used as
blueprints two scenarios formulated by the SETI Project. The first is a
planet orbiting a sun close enough to keep water from freezing out, yet
far enough away to avoid evaporation. The other is a moon orbiting a
gas giant and warmed by twin suns.

By Sean Cooper

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