38 Leda is a large, dark main-belt asteroid that was discovered by French astronomer J. Chacornac on January 12, 1856, and named after Leda, the mother of Helen of Troy in Greek mythology. In the Tholen classification system, it is categorized as a carbonaceous C-type asteroid, while the Bus asteroid taxonomy system lists it as a Cgh asteroid.[4] The spectra of the asteroid displays evidence of aqueous alteration.[5]
.png) A three-dimensional model of 38 Leda based on its light curve | |
| Discovery | |
|---|---|
| Discovered by | J. Chacornac |
| Discovery date | January 12, 1856 |
| Designations | |
Designation | (38) Leda |
| Pronunciation | /ˈliːdə/[1] |
Named after | Leda |
| A904 SF; 1949 QO2 | |
| Main belt | |
| Adjectives | Ledean /lɪˈdiːən/ (Latin Lēdæ-us) |
| Orbital characteristics | |
| Epoch December 31, 2006 (JD 2454100.5) | |
| Aphelion | 472.587 Gm (3.159 AU) |
| Perihelion | 348.232 Gm (2.328 AU) |
| 410.409 Gm (2.743 AU) | |
| Eccentricity | 0.152 |
| 1659.725 d (4.54 a) | |
Average orbital speed | 17.88 km/s |
| 107.567° | |
| Inclination | 6.955° |
| 295.890° | |
| 168.804° | |
| Physical characteristics | |
| Dimensions | 92.255 ± 0.490 km[2] |
| Mass | (7.16 ± 3.38/2.24)×1017 kg[3] |
Mean density | 1.743 ± 0.822/0.544 g/cm3[3] |
| 0.0225 m/s² | |
| 0.0455 km/s | |
| 0.5350 d (12.84 h) [2] | |
| Albedo | 0.055 [2] |
| Temperature | ~170 K |
Spectral type | C[2] |
| 8.32 | |
Leda has been studied by radar.[6] During 2002, 38 Leda was observed by radar from the Arecibo Observatory. The return signal matched an effective diameter of 116 ± 13 km. This is consistent with some asteroid dimensions computed through other means.[7][8] Based upon a light curve that was generated from photometric observations of this asteroid at Pulkovo Observatory, it has a rotation period of 12.834 ± 0.001 hours and varies in brightness by 0.15 ± 0.01 in magnitude.[9]
References
edit- ^ Noah Webster (1884) A Practical Dictionary of the English Language
- ^ a b c d "38 Leda". JPL Small-Body Database. Jet Propulsion Laboratory. SPK-ID: 38. Retrieved 15 June 2008.
- ^ a b Fienga, A.; Avdellidou, C.; Hanuš, J. (February 2020). "Asteroid masses obtained with INPOP planetary ephemerides". Monthly Notices of the Royal Astronomical Society. 492 (1). doi:10.1093/mnras/stz3407.
- ^ DeMeo, Francesca E.; et al. (2011), "An extension of the Bus asteroid taxonomy into the near-infrared" (PDF), Icarus, 202 (1): 160–180, Bibcode:2009Icar..202..160D, doi:10.1016/j.icarus.2009.02.005, archived from the original (PDF) on 17 March 2014, retrieved 12 April 2013. See appendix A.
- ^ Fornasier, S.; et al. (February 1999), "Spectroscopic comparison of aqueous altered asteroids with CM2 carbonaceous chondrite meteorites", Astronomy and Astrophysics Supplement, 135: 65−73, Bibcode:1999A&AS..135...65F, doi:10.1051/aas:1999161.
- ^ "Radar-Detected Asteroids and Comets". NASA/JPL Asteroid Radar Research. Retrieved 30 October 2011.
- ^ Magri, Christopher; et al. (January 2007), "A radar survey of main-belt asteroids: Arecibo observations of 55 objects during 1999–2003", Icarus, 186 (1): 126–151, Bibcode:2007Icar..186..126M, doi:10.1016/j.icarus.2006.08.018
- ^ Carry, B. (December 2012), "Density of asteroids", Planetary and Space Science, 73 (1): 98–118, arXiv:1203.4336, Bibcode:2012P&SS...73...98C, doi:10.1016/j.pss.2012.03.009. See Table 1.
- ^ Pilcher, Frederick (October 2011), "Rotation Period Determinations for 11 Parthenope, 38 Leda, 111 Ate 194 Prokne, 217 Eudora, and 224 Oceana", The Minor Planet Bulletin, 38 (4): 183–185, Bibcode:2011MPBu...38..183P.
External links
edit- 38 Leda at AstDyS-2, Asteroids—Dynamic Site
- 38 Leda at the JPL Small-Body Database