423 Diotima
A three-dimensional model of 423 Diotima based on its light curve. | |
Discovery | |
---|---|
Discovered by | Auguste Charlois |
Discovery date | 7 December 1896 |
Designations | |
Pronunciation | /daɪ.əˈtaɪmə/ |
Named after | Diotima of Mantinea |
1896 DB | |
Main belt | |
Orbital characteristics[1] | |
Epoch 31 July 2016 (JD 2457600.5) | |
Uncertainty parameter 0 | |
Observation arc | 116.96 yr (42719 d) |
Aphelion | 3.18523 AU (476.504 Gm) |
Perihelion | 2.95026 AU (441.353 Gm) |
3.06774 AU (458.927 Gm) | |
Eccentricity | 0.038297 |
5.37 yr (1962.6 d) | |
Average orbital speed | 17.01 km/s |
237.495° | |
0° 11m 0.355s / day | |
Inclination | 11.2304° |
69.4710° | |
200.103° | |
Earth MOID | 1.93679 AU (289.740 Gm) |
Jupiter MOID | 1.85156 AU (276.989 Gm) |
Jupiter Tisserand parameter | 3.201 |
Physical characteristics | |
Dimensions |
208.8 ± 4.9 km (IRAS)[1] 171 x 138 km[2] 211.64 ± 16.02 km[3] |
Mean radius | ±2.45 104.385km |
Mass |
1.6×1019 kg[4][5] ≈5.1×1018? kg[6] (6.91 ± 1.93) × 1018 kg[3] |
Mean density | 1.39 ± 0.50 g/cm3[3] |
4.775 h (0.1990 d)[1] | |
±0.003 0.0515[1] | |
C[1] | |
7.24[1] | |
|
423 Diotima is one of the larger main-belt asteroids. It is classified as a C-type asteroid[1] and is probably composed of primitive carbonaceous material.
It was discovered by Auguste Charlois on December 7, 1896, in Nice. In the late 1990s, a network of astronomers worldwide gathered lightcurve data that was ultimately used to derive the spin states and shape models of 10 new asteroids, including 423 Diotima. The light curve for this asteroid varies "a lot" depending on the position, with the brightness variations ranging from almost zero to up to 0.2 in magnitude.[7][8] Dunham (2002) used 15 chords and obtained an estimated size of 171 x 138 km.[2]
Name
Diotima is named for Diotima of Mantinea, a priestess who was one of Socrates's teachers. It is one of seven of Charlois's discoveries that was expressly named by the Astromomisches Rechen-Institut (Astronomical Calculation Institute).[9]
The name is stressed on the penultimate syllable, /daɪ.əˈtaɪmə/ dy-ə-TY-mə, or as Latin Diotīma.
References
- 1 2 3 4 5 6 7 "JPL Small-Body Database Browser: 423 Diotima (1896 DB)" (2008-09-09 last obs). Retrieved 6 May 2016.
- 1 2 Vasundhara, R; Kuppuswamy, Ramamoorthy; Velu, Venkataramana (2006). "Occultation of 2UCAC 42376428 by (423) Diotima on 2005 March 06". Astronomical Society of India. 34: 21–26. Retrieved 2008-11-30.
- 1 2 3 Carry, B. (December 2012), "Density of asteroids", Planetary and Space Science, 73, pp. 98–118, arXiv:1203.4336, Bibcode:2012P&SS...73...98C, doi:10.1016/j.pss.2012.03.009. See Table 1.
- ↑ Michalak, G. (2001). "Determination of asteroid masses". Astronomy & Astrophysics. 374 (2): 703–711. Bibcode:2001A&A...374..703M. doi:10.1051/0004-6361:20010731. Retrieved 2008-11-10.
- ↑ Michalak2001 assumed masses of perturbing asteroids used in calculations of perturbations of the test asteroids.
- ↑ Using the volume of an ellipsoid of 209x171x138km * an assumed density of 2 g/cm³ yields a mass (m=d*v) of 5.1E+18 kg
- ↑ Durech, J.; et al. (April 2007), "Physical models of ten asteroids from an observers' collaboration network", Astronomy and Astrophysics, 465 (1), pp. 331–337, Bibcode:2007A&A...465..331D, doi:10.1051/0004-6361:20066347.
- ↑ Durech, J.; Kaasalainen, M.; Marciniak, A.; Allen, W. H. et al. “Asteroid brightness and geometry,” Astronomy and Astrophysics, Volume 465, Issue 1, April I 2007, pp. 331-337.
- ↑ Schmadel Lutz D. Dictionary of Minor Planet Names (fifth edition), Springer, 2003. ISBN 3-540-00238-3.
External links
- Orbital simulation from JPL (Java) / Ephemeris
- 423 Diotima at the JPL Small-Body Database