| Minorplanet: | yes |
| Background: |
|
| 164 Eva | |
| Discovered: | 12 July 1876 |
| Mpc Name: | (164) Eva |
| Alt Names: | A876 NA |
| Named After: | Unknown |
| Epoch: | 31 July 2016 (JD 2457600.5) |
| Semimajor: | 2.6338AU |
| Perihelion: | 1.7188AU |
| Aphelion: | 3.5444abbr=onNaNabbr=on |
| Eccentricity: | 0.34577 |
| Period: | 4.27 yr (1561.2 d) |
| Inclination: | 24.4564° |
| Asc Node: | 76.8519° |
| Arg Peri: | 283.9561° |
| Dimensions: | 101.77 ± 3.61 km |
| Density: | 1.68 ± 1.41 g/cm3 |
| Surface Grav: | 2.249 cm/s (mean) |
| Escape Velocity: | 4.857 cm/s (mean) |
| Rotation: | 13.66abbr=onNaNabbr=on 13.672 h |
| Abs Magnitude: | 8.89, 8.84 |
| Single Temperature: | 170 K (mean) |
| Mean Motion: | / day |
| Observation Arc: | 118.93 yr (43438 d) |
| Uncertainty: | 0 |
| Moid: | 0.882286AU |
| Jupiter Moid: | 2.44116AU |
| Tisserand: | 3.191 |
164 Eva is a main-belt asteroid that was discovered by the French brothers Paul Henry and Prosper Henry on July 12, 1876, in Paris. The reason the name Eva was chosen remains unknown, though Karl Ludwig Littrow suspected a "worldly origin" ("Mit dem Namen könnten wir wie bei Miriam wieder den biblischen Boden zu betreten glauben, wenn wir bei diesem Entdecker nicht an Taufen weltlichen Ursprungs gewöhnt wären"). The orbital elements for 164 Eva were published in 1877 by American astronomer Winslow Upton. It is categorized as a C-type asteroid and is probably composed of primitive carbonaceous chondritic materials.
Photometric observations of this asteroid at the Palmer Divide Observatory in Colorado Springs, Colorado, during 2008 gave a light curve with a period of 13.672 ± 0.003 hours and a small brightness variation of 0.04 ± 0.01 in magnitude. This is consistent with a previous study reported in 1982 that listed a period estimate of 13.66 hours.
Between 2000 and 2021, 164 Eva has been observed to occult fourteen stars.
With a perihelion of 1.718 AU 164 Eva is the closest asteroid over 100 kilometers to approach the orbit of Mars. Its closest approach is about 0.05 AU or about 19.5 lunar distances.[1]