Green Lantern Corps vs Nova Corps
The Green Lantern Corp debuted in 1959 as the DC Universe’s intergalactic police force. Green Lanterns patrol the universe under the guidance of the Guardians and utilize the power of their green lantern rings that draw power from the wearers willpower.
The Nova Corps debuted in 1979 and the Marvel equivalent of the Green Lantern Corps as they, too, are an intergalactic policing force. Based on Xandar, the corps derives its power from the Living Computers of Xandar known as the Xandarian Worldmind.