29558

29558 is the provisional designation of a minor planet located in the main asteroid belt between Mars and Jupiter. The object was first observed on 20 December 1999 by astronomers at the Tzec Maun Observatory in Chile and subsequently confirmed at the Siding Spring Observatory in Australia. Its discovery observation was recorded under the designation 1999 EG, and it was later given the permanent number 29558 by the Minor Planet Center after its orbit was reliably determined.

The asteroid follows a typical inner main-belt orbit, with a semi-major axis of approximately 2.3 astronomical units, an eccentricity of about 0.15, and an inclination of roughly 4 degrees relative to the ecliptic. These orbital elements place it among the population of S-type and C-type bodies that dominate this region of the solar system. Photometric studies indicate a rotation period around 5 hours, suggesting a relatively compact shape and a non‑spherical body. Its absolute magnitude is reported at 15.6, which corresponds to an estimated diameter of roughly 3 to 4 kilometers, assuming a standard albedo.

29558 is part of the many numbered minor planets catalogued by the International Astronomical Union. While it has not been the subject of extensive scientific observation beyond its initial discovery and orbit determination, it serves as a representative example of the numerous belt objects monitored by astronomers to better understand the composition and dynamical evolution of the asteroid belt.