511 Davida
3D model of Davida based on lightcurve modeling | |
Discovery | |
---|---|
Discovered by | R. S. Dugan |
Discovery date | May 30, 1903 |
Designations | |
MPC designation | (511) Davida |
Pronunciation | /dəˈvaɪdə/[1] or /ˈdævɪdə/[2] |
Named after | David Peck Todd |
1903 LU | |
main-belt · (outer) Meliboea [3] | |
Orbital characteristics[4] | |
Epoch August 27, 2011 (JD 2455800.5) | |
Aphelion | 3.756248648 AU |
Perihelion | 2.57323875 AU |
3.164743701 AU | |
Eccentricity | 0.18690453 |
5.63009883 yr (2056.393597 d) | |
202.86548° | |
Inclination | 15.942247° |
107.63617° | |
338.17810° | |
Physical characteristics | |
Dimensions | km × 294 km × 231 km 357[5] |
Mean diameter | ±21 km 289[5] |
Mass | ±0.20 3.84×1019 kg[6] |
Mean density | ±1.30 g/cm³ 2.97[6] |
0.2137235 d (5.13 h) | |
Albedo | 0.054–0.066 2 |
Temperature | ~160 K |
Spectral type | C |
9.50[7] to 12.98 | |
6.22 | |
|
511 Davida is a large C-type asteroid in the asteroid belt. It was discovered by R. S. Dugan in 1903. It is one of the ten most-massive asteroids, and the 7th-largest asteroid. Davida is named after David Peck Todd, an astronomy professor at Amherst College.
Description
It is approximately 270–310 km in diameter and comprises an estimated 1.5% of the total mass of the asteroid belt.[6][8][9] It is a C-type asteroid, which means that it is dark in colouring with a carbonaceous chondrite composition.
Davida is one of the few main-belt asteroids whose shape has been determined by ground-based visual observation. From 2002 to 2007, astronomers at the Keck Observatory used the Keck II telescope, which is fitted with adaptive optics, to photograph Davida. The asteroid is not a dwarf planet: there are at least two promontories and at least one flat facet with 15-km deviations from a best-fit ellipsoid. The facet is presumably a 150-km global-scale crater like the ones seen on 253 Mathilde. Conrad et al. (2007) show that craters of this size "can be expected from the impactor size distribution, without likelihood of catastrophic disruption of Davida."
Mass
In 2001, Michalak estimated Davida to have a mass of (±0.56) 6.64×1019 kg[10][11] In 2007, Baer and Chesley estimated Davida to have a mass of (±0.6) 5.9×1019 kg.[12] As of 2010, Baer suggests Davida has a mass of (±0.20) 3.84×1019 kg.[6] This most recent estimate by Baer suggests that Davida is less massive than 704 Interamnia, making Davida the sixth-most-massive asteroid, though the error bars overlap.[6]
Occultations
There have been 9 occultation events observed since 1987, many of which produced two or three chords.[13] Two examples shown here.
References
- ↑ from Latin Dāvīda
- ↑ də-VY-də or DAV-i-də
- ↑ "Small Bodies Data Ferret". Nesvorny HCM Asteroid Families V3.0. Retrieved 2 September 2017.
- ↑ JPL data Retrieved 2011-09-02
- 1 2 Conrad (2007). Measurements of the short axis are less precise than the other two, but also involve a discrepancy between fitting the convolved and deconvolved images (±40 km), and fitting the edges ( 241±114 km). 191
- 1 2 3 4 5 Baer, James (2010). "Recent Asteroid Mass Determinations". Personal Website. Retrieved 2011-02-13.
- ↑ "Bright Minor Planets 2003". Minor Planet Center. Retrieved 2008-05-21.
- ↑ Pitjeva, E. V. (2005). "High-Precision Ephemerides of Planets—EPM and Determination of Some Astronomical Constants" (PDF). Solar System Research. 39 (3): 176. Bibcode:2005SoSyR..39..176P. doi:10.1007/s11208-005-0033-2. Archived from the original (PDF) on October 31, 2008.
- ↑ "Baer Mass of 511 Davida" 0.220 / "Mass of Mbelt" 15 = 0.0146
- ↑ Michalak, G. (2001). "Determination of asteroid masses (6) Hebe, (10) Hygiea, (15) Eunomia, (52) Europa, (88) Thisbe, (444) Gyptis, (511) Davida and (704) Interamnia". Astronomy & Astrophysics. 374: 703–711. Bibcode:2001A&A...374..703M. doi:10.1051/0004-6361:20010731. Archived from the original on 2012-12-04. Retrieved 2008-11-04.
- ↑ (±0.28) 3.34×10−11 solar masses, per Michalak (2001), extended dynamic model.
- ↑ Baer, James; Steven R. Chesley (2007). "Astrometric masses of 21 asteroids, and an integrated asteroid ephemeris" (PDF). Celestial Mechanics and Dynamical Astronomy. Springer Science+Business Media B.V. 2007. 100 (2008): 27–42. Bibcode:2008CeMDA.100...27B. doi:10.1007/s10569-007-9103-8. Retrieved 2008-11-15.
(±0.30) 2.98×10−11 solar masses
- ↑ "PDS Asteroid/Dust Subnode". sbn.psi.edu. Archived from the original on April 25, 2018. Retrieved April 27, 2018.
External links
Wikimedia Commons has media related to 511 Davida. |
- Asteroid occultations, IOTA – International Occultation Timing Association (2011)
- Time lapse photography of Davida
- Al Conrad's research page at Keck
- 511 Davida at the JPL Small-Body Database