Discovery | |
---|---|
Discovered by | C. H. F. Peters |
Discovery date | 20 February 1876 |
Designations | |
(160) Una | |
Pronunciation | /ˈjuːnə/ [1] |
Main belt | |
Orbital characteristics [2] | |
Epoch 31 July 2016 ( JD 2457600.5) | |
Uncertainty parameter 0 | |
Observation arc | 118.30 yr (43209 d) |
Aphelion | 2.90877 AU (435.146 Gm) |
Perihelion | 2.54727 AU (381.066 Gm) |
2.72802 AU (408.106 Gm) | |
Eccentricity | 0.066257 |
4.51 yr (1645.8 d) | |
Average
orbital speed | 18.01 km/s |
144.472 ° | |
0° 13m 7.471s / day | |
Inclination | 3.82512° |
8.60989° | |
52.8418° | |
Earth MOID | 1.56031 AU (233.419 Gm) |
Jupiter MOID | 2.30107 AU (344.235 Gm) |
TJupiter | 3.349 |
Physical characteristics | |
Dimensions | 81.24±2.1 km |
Mass | 5.6×1017 kg (assumed) |
Mean
density | 2.0? g/cm3 |
Equatorial
surface gravity | 0.0227 m/s2 |
Equatorial
escape velocity | 0.0429 km/s |
11.033
h (0.4597
d)
[2] 0.234 d (5.61 h) [3] [4] | |
0.0625±0.003
[2] 0.063 [5] | |
Temperature | ~170 K |
C [6] | |
9.08, [2] 8.95 [7] | |
160 Una is a fairly large and dark, primitive Main belt asteroid that was discovered by German-American astronomer C. H. F. Peters on February 20, 1876, in Clinton, New York. [8] It is named after a character in Edmund Spenser's epic poem The Faerie Queene (1590).
In the Tholen classification system it is categorized as a CX-type, while the Bus asteroid taxonomy system lists it as an Xk asteroid. [9] Photometric observations of this asteroid made at the Torino Observatory in Italy during 1990–1991 were used to determine a synodic rotation period of 5.61 ± 0.01 hours. [3]