25 Phocaea
.png?lang=en) A three-dimensional model of 25 Phocaea based on its light curve. | |
| Discovery | |
|---|---|
| Discovered by | J. Chacornac |
| Discovery date | April 6, 1853 |
| Designations | |
Designation | (25) Phocaea |
| Pronunciation | /foʊˈsiːə/ foh-SEE-ə |
Named after | Phōcæa |
| 1956 GC | |
| Main belt (Phocaea family) | |
| Orbital characteristics | |
| Epoch June 14, 2006 (JD 2453900.5) | |
| Aphelion | 450.716 Gm (3.013 AU) |
| Perihelion | 267.314 Gm (1.787 AU) |
| 359.015 Gm (2.400 AU) | |
| Eccentricity | 0.255 |
| 1357.936 d (3.72 a) | |
Average orbital speed | 18.91 km/s |
| 6.932° | |
| Inclination | 21.584° |
| 214.258° | |
| 90.154° | |
| Physical characteristics | |
| Dimensions | 75.1 ± 3.6 km (IRAS)[1] 80.19 ± 4.66 km[2] |
| Mass | (5.99 ± 0.60) × 1017 kg[2] |
Mean density | 2.21 ± 0.44 g/cm3[2] |
| 0.0210? m/s² | |
| 0.0397? km/s | |
| 0.4144 d (9.945 h)[1][3] | |
| Albedo | 0.231[1][4] |
| Temperature | ~173 K |
Spectral type | S[1] |
| 7.83[1] | |
25 Phocaea is a main-belt asteroid. It was discovered by J. Chacornac at Marseille, on April 6. 1853. It was his first asteroid discovery out of a total of six. It is named after Phocaea, the Greek name of Foça in Turkey, whence the founders of Marseille came.
Phocaea has been studied by radar.[5] Photometric observations of this asteroid at the Organ Mesa Observatory in Las Cruces, New Mexico during 2010 gave a light curve with a period of 9.9341 ± 0.0002 hours. The brightness near the deepest minimum of the light curve showed changes with phase angle, which is the result of shadows extending across surface irregularities.[6]
References
- ^ a b c d e "JPL Small-Body Database Browser: 25 Phocaea" (2011-12-30 last obs). Jet Propulsion Laboratory. Retrieved 2012-01-26.
- ^ a b c Carry, B. (December 2012), "Density of asteroids", Planetary and Space Science, vol. 73, pp. 98–118, arXiv:1203.4336, Bibcode:2012P&SS...73...98C, doi:10.1016/j.pss.2012.03.009. See Table 1.
- ^ http://www.psi.edu/pds/asteroid/EAR_A_5_DDR_DERIVED_LIGHTCURVE_V8_0/data/lc.tab
- ^ http://www.psi.edu/pds/asteroid/EAR_A_5_DDR_ALBEDOS_V1_1/data/albedos.tab
- ^ "Radar-Detected Asteroids and Comets". NASA/JPL Asteroid Radar Research. Retrieved 2011-10-30.
- ^ Pilcher, Frederick (April 2011), "Rotation Period Determinations for 25 Phocaea, 140 Siwa, 149 Medusa 186 Celuta, 475 Ocllo, 574 Reginhild, and 603 Timandra", The Minor Planet Bulletin, vol. 38, no. 2, pp. 76–78, Bibcode:2011MPBu...38...76P.
