3430 Bradfield
Discovery [1] | |
---|---|
Discovered by | C. Shoemaker |
Discovery site | Palomar Obs. |
Discovery date | 9 October 1980 |
Designations | |
MPC designation | (3430) Bradfield |
Named after |
William A. Bradfield (discoverer of comets) |
1980 TF4 · 1974 HY1 1976 YS7 | |
main-belt [1][2] · (middle) Agnia [3] | |
Orbital characteristics [2] | |
Epoch 23 March 2018 (JD 2458200.5) | |
Uncertainty parameter 0 | |
Observation arc | 43.93 yr (16,044 d) |
Aphelion | 3.0293 AU |
Perihelion | 2.4890 AU |
2.7592 AU | |
Eccentricity | 0.0979 |
4.58 yr (1,674 d) | |
102.11° | |
0° 12m 54s / day | |
Inclination | 4.4281° |
43.225° | |
278.60° | |
Physical characteristics | |
Mean diameter | ±0.263 km 8.492[4] |
±0.035 0.269[4] | |
SMASS = Sq [2] | |
12.5[2] | |
|
3430 Bradfield, provisional designation 1980 TF4, is a stony Agnia asteroid from the central regions of the asteroid belt, approximately 8 kilometers (5 miles) in diameter. It was discovered on 9 October 1980, by American astronomer Carolyn Shoemaker at the Palomar Observatory in California. The Sq-type asteroid was named after comet hunter William A. Bradfield.[1]
Orbit and classification
Bradfield is a member of the Agnia family (514),[3] a very large family of stony asteroids with more than 2000 known members.[5] They most likely formed from the breakup of a basalt object, which in turn was spawned from a larger parent body that underwent igneous differentiation.[6] The family's parent body and namesake is the asteroid 847 Agnia.[5]
It orbits the Sun in the central main-belt at a distance of 2.5–3.0 AU once every 4 years and 7 months (1,674 days; semi-major axis of 2.76 AU). Its orbit has an eccentricity of 0.10 and an inclination of 4° with respect to the ecliptic.[2] The body's observation arc begins with its observations as 1974 HY1 at Cerro El Roble Observatory in April 1974, more than 6 years prior to its official discovery observation at Palomar.[1]
Physical characteristics
In the SMASS classification, Bradfield is an Sq-subtype, that transitions between the common, stony S-type and Q-type asteroids.[2]
Diameter and albedo
According to the survey carried out by the NEOWISE mission of NASA's Wide-field Infrared Survey Explorer, Bradfield measures 8.492 kilometers in diameter and its surface has an albedo of 0.269.[4]
Rotation period
As of 2018, no rotational lightcurve of Bradfield has been obtained from photometric observations. The body's rotation period, pole and shape remain unknown.[2]
Naming
This minor planet was named after New Zealand-born Australian amateur astronomer and rocket engineer William A. Bradfield (1927–2014). A discoverer of several comets himself, he significantly increased the rate of discovery of bright comets from the southern hemisphere during the 1970s and 1980s.[1] The official naming citation was published by the Minor Planet Center on 14 April 1987 (M.P.C. 11750).[7]
References
- 1 2 3 4 5 "3430 Bradfield (1980 TF4)". Minor Planet Center. Retrieved 12 April 2018.
- 1 2 3 4 5 6 7 "JPL Small-Body Database Browser: 3430 Bradfield (1980 TF4)" (2018-03-28 last obs.). Jet Propulsion Laboratory. Retrieved 12 April 2018.
- 1 2 "Small Bodies Data Ferret". Nesvorny HCM Asteroid Families V3.0. Retrieved 12 April 2018.
- 1 2 3 Masiero, Joseph R.; Mainzer, A. K.; Grav, T.; Bauer, J. M.; Cutri, R. M.; Dailey, J.; et al. (November 2011). "Main Belt Asteroids with WISE/NEOWISE. I. Preliminary Albedos and Diameters". The Astrophysical Journal. 741 (2): 20. arXiv:1109.4096. Bibcode:2011ApJ...741...68M. doi:10.1088/0004-637X/741/2/68. Retrieved 12 April 2018.
- 1 2 Nesvorný, D.; Broz, M.; Carruba, V. (December 2014). "Identification and Dynamical Properties of Asteroid Families" (PDF). Asteroids IV: 297–321. arXiv:1502.01628. Bibcode:2015aste.book..297N. doi:10.2458/azu_uapress_9780816532131-ch016. Retrieved 12 April 2018.
- ↑ Sunshine, Jessica M.; Bus, Schelte J.; McCoy, Timothy J.; Burbine, Thomas H.; Corrigan, Catherine M.; Binzel, Richard P. (August 2004). "High-calcium pyroxene as an indicator of igneous differentiation in asteroids and meteorites". Meteoritics and Planetary Science. 39 (8): 1343–1357. Bibcode:2004M&PS...39.1343S. doi:10.1111/j.1945-5100.2004.tb00950.x. Retrieved 12 April 2018.
- ↑ "MPC/MPO/MPS Archive". Minor Planet Center. Retrieved 12 April 2018.
External links
- Dictionary of Minor Planet Names, Google books
- Discovery Circumstances: Numbered Minor Planets (1)-(5000) – Minor Planet Center
- 3430 Bradfield at AstDyS-2, Asteroids—Dynamic Site
- 3430 Bradfield at the JPL Small-Body Database