773 Irmintraud
773 Irmintraud, provisional designation 1913 TV, is a dark and reddish, rare-type asteroid from the outer region of the asteroid belt, about 92 kilometers in diameter. It was discovered on 22 December 1913, by German astronomer Franz Kaiser at Heidelberg Observatory in southern Germany.
| Discovery | |
|---|---|
| Discovered by | F. Kaiser |
| Discovery site | Heidelberg Obs. |
| Discovery date | 22 December 1913 |
| Designations | |
MPC designation | (773) Irmintraud |
| Pronunciation | German: [ˈɪʁmɪntʁaʊt] |
Named after | Irmtraud (German given-name) |
Alternative designations | 1913 TV · 1946 SO A910 CG |
Minor planet category | main-belt · (outer) |
| Orbital characteristics | |
| Epoch 31 July 2016 (JD 2457600.5) | |
| Uncertainty parameter 0 | |
| Observation arc | 102.32 yr (37372 d) |
| Aphelion | 3.0876 AU (461.90 Gm) |
| Perihelion | 2.6294 AU (393.35 Gm) |
Semi-major axis | 2.8585 AU (427.63 Gm) |
| Eccentricity | 0.080135 |
Orbital period (sidereal) | 4.83 yr (1765.2 d) |
Mean anomaly | 220.21° |
Mean motion | 0° 12m 14.184s / day |
| Inclination | 16.684° |
Longitude of ascending node | 322.41° |
| 331.91° | |
| Earth MOID | 1.62349 AU (242.871 Gm) |
| Jupiter MOID | 2.21251 AU (330.987 Gm) |
| TJupiter | 3.236 |
| Physical characteristics | |
| Dimensions | 95.88 km 87.07±1.76 km 91.67±0.90 km |
Mean radius | 47.94±0.9 km |
Synodic rotation period | 6.7514 h (0.28131 d) 6.750±0.002 h 6.75 h 6.746±0.004 h 6.748±0.001 h |
| 0.0440 0.053±0.003 0.048±0.006 0.0440±0.002 | |
| B–V = 0.706 U–B = 0.284 D (Tholen), T (SMASS) T | |
| 9.10 | |
The asteroid is classified as a D-type and T-type body in the Tholen and SMASS taxonomy, respectively. The rare spectral T-type is similar to D-types which are often found among Jupiter trojans thought to have originated from the Kuiper belt. It orbits the Sun at a distance of 2.6–3.1 AU once every 4 years and 10 months (1,763 days). Its orbit is tilted by 17 degrees to the plane of the ecliptic and shows a low eccentricity of 0.08. According to the surveys carried out by the Infrared Astronomical Satellite, IRAS, the Japanese Akari satellite, and the Wide-field Infrared Survey Explorer with its subsequent NEOWISE mission, the minor planet's low albedo lies in the range of 0.04–0.05. It has a well-defined rotation period of 6.75 hours, determined by several concurring observations.
773 Irmintraud commemorates the antiquated German feminine name, Irmtraud, that appears frequently in old songs and sagas. The asteroid is a likely source of the Tagish Lake meteorite which landed in Canada on January 18, 2000.