4904 Makio, provisional designation , is a stony asteroid from the inner regions of the asteroid belt, approximately 8 kilometers in diameter. It was discovered by Japanese astronomers Yoshikane Mizuno and Toshimasa Furuta at Kani Observatory () on 21 November 1989. It was named after Japanese astronomer Makio Akiyama.
Makio orbits the Sun in the inner main-belt at a distance of 2.1âÂÂ2.7 AU once every 3 years and 8 months (1,348 days). Its orbit has an eccentricity of 0.13 and an inclination of 10ð with respect to the ecliptic.
It was first identified as at the Chilean Cerro El Roble Station in 1974, extending the body's observation arc by 15 years prior to its discovery.
Makio has been characterized as a common S-type asteroid.
A rotational lightcurve of Makio was obtained from photometric observations made by Julian Oey at the Australian Kingsgrove Observatory () in March 2009. Lightcurve analysis gave a rotation period of hours with a small brightness variation of 0.08 magnitude, indicative of a spheroidal shape ().
According to the survey carried out by the NEOWISE mission of NASA's Wide-field Infrared Survey Explorer, Makio measures 7.0 kilometers in diameter and its surface has an albedo of 0.33, while the Collaborative Asteroid Lightcurve Link assumes a standard albedo for stony asteroids of 0.20 and calculates a diameter of 9.4 kilometers with an absolute magnitude of 12.5.
This minor planet was named after Japanese astronomer Makio Akiyama (born 1950), an observer and discoverer of minor planets himself at the Susono Observatory (). The official naming citation was published by the Minor Planet Center on 5 March 1996 ().