163693 Atira (/əˈtɪrə/; provisional designation 2003 CP20) is a stony asteroid, dwelling in the interior of Earth's orbit.

The primary component with a diameter of approximately 4.8 kilometers (3 miles)[7] is orbited by a minor-planet moon that measures about 1 km (0.6 mi).

[13] Atiras are similar to the larger group of Aten asteroids, as both are near-Earth objects and both have a semi-major axis smaller than that of Earth (< 1.0 AU).

[3] Atira is a S-type asteroid and orbits the Sun at a distance of 0.5–1.0 AU once every 8 months (233 days).

Images taken at Arecibo Observatory on 20 January 2017 revealed that Atira is a synchronous binary asteroid with a minor-planet moon.

The other classes of near-Earth asteroids, Amors, Apollos, and Atens, are named after a Roman, Greek, and Egyptian god respectively, each of which begins with the letter 'A'.