.png) A three-dimensional model of 32 Pomona based on itslight curve | |
| Discovery | |
|---|---|
| Discovered by | H. Goldschmidt |
| Discovery date | 26 October 1854 |
| Designations | |
| (32) Pomona | |
| Pronunciation | /pəˈmoʊnə/[1] |
Named after | Pōmōna |
| A899 QA; A911 KF; 1945 RB; 1949 SH; 1950 YD | |
| Main belt | |
| Adjectives | Pomonian/pəˈmoʊniən/ |
| Orbital characteristics[2] | |
| Epoch December 31, 2006 (JD 2454100.5) | |
| Aphelion | 419.316 Gm (2.803 AU) |
| Perihelion | 354.967 Gm (2.373 AU) |
| 387.142 Gm (2.588AU) | |
| Eccentricity | 0.083 |
| 1520.602 d (4.16a) | |
| 46.086° | |
| Inclination | 5.530° |
| 220.574° | |
| 2023-Feb-05 | |
| 339.680° | |
| Physical characteristics | |
| Dimensions | 80.76±1.6 km[2] |
| Mass | (8.88 ± 4.17/1.67)×1017 kg[3] |
Meandensity | 3.102 ±1.455/0.584 g/cm3[3][a] |
| 0.3937 d (9.448 h)[2] | |
| 0.2564[2] | |
| S[2] | |
| 7.79[2] | |
32 Pomona (/pəˈmoʊnə/ ⓘpə-MOH-nə;[4]) is a stonymain-beltasteroid that is 81 kilometres (50 mi) in diameter. It was discovered by German-French astronomerHermann Mayer Salomon Goldschmidt on October 26, 1854,[5] and is named afterPōmōna, theRoman goddess offruit trees.
Photometric observations of this asteroid gave alight curve with a synodicrotation period of 9.448 hours. The data was used to construct a model for the asteroid, revealing it to be an angular object that is spinning about a pole withecliptic coordinates (β, λ) = (+58°, 267°). The ratio of the major to minor axes' lengths is roughly equal to 1.3.[6]
The spectrum of 32 Pomona matches anS-type in theTholen classification system, and is similar to primitiveachondrite meteorites.[7] Measurements of thethermal inertia of 32 Pomona give a value of around 20–120 m−2 K−1 s−1/2, compared to 50 forlunar regolith and 400 for coarse sand in an atmosphere.[8]
Australian amateur astronomer Jonathan Bradshaw recorded an unusualasteroid occultation by 32 Pomona on 16 August 2008. The expected maximum duration of the occultation was 7.1 secs; however, the video recording shows two separate occultations of equal depth each lasting 1.2 seconds, separated by 0.8 secs. Those durations convert tochord lengths at the asteroid of 15 km, 10 km, and 15 km – for a total length of 40 km.[9] TheIRAS diameter for Pomona is 80.76 ± 1.6 km.[2] The most likely explanation for this observation is that the asteroid is eitherbinary (including a contact binary), or is a unitary asteroid with a significant concave region on its surface.[9][10] The video of this occultation can be viewed onYouTube.
