9903 Leonhardt is a main belt asteroid

Asteroid belt

The asteroid belt is the region of the Solar System located roughly between the orbits of the planets Mars and Jupiter. It is occupied by numerous irregularly shaped bodies called asteroids or minor planets...

. It has an eccentricity

Orbital eccentricity

The orbital eccentricity of an astronomical body is the amount by which its orbit deviates from a perfect circle, where 0 is perfectly circular, and 1.0 is a parabola, and no longer a closed orbit...

 of 0.245 and an orbital period of 5.40 years. Leonhardt has an average orbital speed of approximately 16.987 km/s and an inclination of 1.68°.

It was discovered on July 4, 1997 by Paul Comba

Paul G. Comba

Paul G. Comba is an Italian-American astronomer.He was born in 1926 in Italy and went to the United States in 1946 at the age of 20 on a scholarship to Caltech from which he received a Ph.D. in mathematics in 1951. After graduation he taught at the University of Hawaii until 1960, when he joined...

 at the Prescott Observatory

Prescott Observatory

Prescott Observatory was built by Paul G. Comba and is now owned and operated by Matt Francis. The observatory is located south of Prescott Arizona and is dedicated to the study of cosmology. Refurbished in 2011, the observatory houses a PlaneWave CDK 24 inch telescope with two Takahashi wide...

. Originally given the provisional designation "", it was renamed "Leonhardt" after Gustav Leonhardt

Gustav Leonhardt

Gustav Leonhardt is a highly renowned Dutch keyboard player, conductor, musicologist, teacher and editor. Leonhardt has been a leading figure in the movement to perform music on period instruments...

, the eminent Dutch harpsichordist

Harpsichordist

A harpsichordist is a person who plays the harpsichord.Many baroque composers played the harpsichord, including Johann Sebastian Bach, Domenico Scarlatti, George Frideric Handel, François Couperin and Jean-Philippe Rameau...

, conductor and pedagogue.