In Greek mythology, Arcas (; Ἀρκάς) was the son of Zeus and Callisto. Callisto was a nymph in the retinue of the goddess Artemis. As she would not be with anyone but Artemis, Zeus cunningly disguised himself as Artemis and seduced Callisto. The child resulting from their union was called Arcas.

Arcas — also designated ARCAS — was the designation of an American sounding rocket, which was launched between July 31, 1959 and August 9, 1991 at least 421 times. The Arcas has a maximum flight altitude of 52 kilometers, a takeoff thrust of 1.5 kN, a takeoff weight of 34 kilograms, and a diameter of 11 centimeters. The Arcas was 2.30 m long and had a fin span of 0.33 m.