| Minorplanet: | yes |
| Background: |
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| 990 Yerkes | |
| Mpc Name: | (990) Yerkes |
| Alt Names: | 1922 MZ |
| Discovered: | 23 November 1922 |
| Orbit Ref: | [1] |
| Observation Arc: | 102.46 yr (37425 days) |
| Uncertainty: | 0 |
| Epoch: | 31 July 2016 (JD 2457600.5) |
| Eccentricity: | 0.21652 |
| Semimajor: | 2.6696AU |
| Perihelion: | 2.0916AU |
| Aphelion: | 3.2477abbr=onNaNabbr=on |
| Period: | 4.36 yr (1593.2 d) |
| Inclination: | 8.7872° |
| Asc Node: | 353.971° |
| Arg Peri: | 9.4832° |
| Mean Motion: | / day |
| Abs Magnitude: | 11.7 |
| Rotation: | 24.56abbr=onNaNabbr=on |
| Mean Radius: | km |
990 Yerkes is a main belt asteroid discovered by Belgian-American astronomer George Van Biesbroeck in 1922, and named after the Yerkes Observatory.
Photometric observations of this asteroid collected during 2009 show a rotation period of 24.45 ± 0.05 hours with a brightness variation of 0.35 ± 0.05 magnitude.