174 Phaedra
Phaedra (minor planet designation: 174 Phaedra) is a sizable, rocky main belt asteroid that was discovered by Canadian-American astronomer James Craig Watson on September 2, 1877, and named after Phaedra, the tragic lovelorn queen in Greek mythology.
A three-dimensional model of 174 Phaedra based on its light curve. | |
| Discovery | |
|---|---|
| Discovered by | J. C. Watson |
| Discovery date | 2 September 1877 |
| Designations | |
MPC designation | (174) Phaedra |
| Pronunciation | /ˈfiːdrə/ |
Alternative designations | A877 RA |
Minor planet category | Main belt |
| Orbital characteristics | |
| Epoch 31 July 2016 (JD 2457600.5) | |
| Uncertainty parameter 0 | |
| Observation arc | 138.61 yr (50629 d) |
| Aphelion | 3.2658 AU (488.56 Gm) |
| Perihelion | 2.4572 AU (367.59 Gm) |
Semi-major axis | 2.8615 AU (428.07 Gm) |
| Eccentricity | 0.14128 |
Orbital period (sidereal) | 4.84 yr (1768.0 d) |
Mean anomaly | 330.70° |
Mean motion | 0° 12m 13.032s / day |
| Inclination | 12.124° |
Longitude of ascending node | 327.69° |
| 289.08° | |
| Earth MOID | 1.47439 AU (220.566 Gm) |
| Jupiter MOID | 1.99981 AU (299.167 Gm) |
| TJupiter | 3.254 |
| Physical characteristics | |
Mean radius | 34.62±2.2 km |
Synodic rotation period | 5.744 h (0.2393 d) |
| 0.1495±0.021 | |
| S | |
| 8.48 | |
The asteroid is orbiting the Sun with a period of 4.84 years and an eccentricity of 0.14. Lightcurve data obtained from Phaedra indicates a rather irregular or elongated body. It has a cross-section size of ~35 km. Photometric observations of this asteroid at the Shadowbox Observatory in Carmel, Indiana, during 2009 gave a light curve with a period of 4.96 ± 0.01 hours. This is consistent with previous studies in 1977, 1988, and 2008. The asteroid's pole of rotation lies just 5–16° away from the plane of the ecliptic.