The luna moth is a lime-green, Nearctic Saturniid moth in the family Saturniidae, subfamily Saturniinae. It has a wingspan of up to 114 mm, making it one of the largest moths in North America

Hindwings have long curving tails.

Wings are pale green, each with a transparent eyespot.

Outer margins are pink in the southern spring brood, yellow in the southern summer brood and in northern populations.