| Minorplanet: | yes |
| 1704 Wachmann | |
| Background: |
|
| Discovered: | 7 March 1924 |
| Mpc Name: | (1704) Wachmann |
| Alt Names: | A924 EE1947 CE 1957 BJ |
| Named After: | Arno Wachmann |
| Epoch: | 4 September 2017 (JD 2458000.5) |
| Uncertainty: | 0 |
| Observation Arc: | 93.16 yr (34,026 days) |
| Perihelion: | 2.0292 AU |
| Semimajor: | 2.2228 AU |
| Eccentricity: | 0.0871 |
| Period: | 3.31 yr (1,210 days) |
| Mean Motion: | / day |
| Inclination: | 0.9715° |
| Asc Node: | 259.47° |
| Arg Peri: | 280.77° |
| Dimensions: | km 7.82 km |
| Albedo: | 0.20 |
| Abs Magnitude: | 12.913.3 |
1704 Wachmann, provisional designation, is a stony asteroid from the inner regions of the asteroid belt, approximately 7 kilometers in diameter. It was discovered by German astronomer Karl Reinmuth at Heidelberg Observatory on 7 March 1924. It was later named after astronomer Arno Wachmann.
The S-type asteroid orbits the Sun in the inner main-belt at a distance of 2.0–2.4 AU once every 3 years and 4 months (1,210 days). Its orbit has an eccentricity of 0.09 and an inclination of 1° with respect to the ecliptic. No precoveries were taken. The asteroid's observation arc begins 3 days after its official discovery observation.
In April 2007, a rotational lightcurve Wachmann was obtained at the U.S. Sandia View Observatory in New Mexico . Lightcurve analysis gave a well-defined rotation period of hours with a brightness variation of 0.40 magnitude .
According to the survey carried out by the NEOWISE mission of NASA's Wide-field Infrared Survey Explorer, Wachmann measures 6.6 and 6.9 kilometers in diameter, and its surface has an albedo of 0.177 and 0.193, respectively, while the Collaborative Asteroid Lightcurve Link assumes a standard albedo for stony asteroids of 0.20 and calculates a diameter of 7.8 kilometers, based on an absolute magnitude of 12.9.
This minor planet was named for Arno Wachmann (1902–1990), long-time astronomer at the Bergedorf Observatory in Hamburg, discoverer of minor planets and comets, and observer of variable and binary stars. He is best known for the co-discovery of the three "Schwassmann–Wachmann" comets, 29P, 31P and 73P. The official was published by the Minor Planet Center on 20 February 1976 .