_Hestia.png) 3D convex shape model of 46 Hestia | |
| Discovery | |
|---|---|
| Discovered by | Norman Robert Pogson |
| Discovery date | August 16, 1857 |
| Designations | |
| (46) Hestia | |
| Pronunciation | /ˈhɛstiə/[1] |
Named after | Hestia |
| main belt | |
| Orbital characteristics[2] | |
| Epoch December 31, 2006 (JD 2454100.5) | |
| Aphelion | 2.961AU (442.886 Gm) |
| Perihelion | 2.091 AU (312.736 Gm) |
| 2.526 AU (377.811 Gm) | |
| Eccentricity | 0.172 |
| 4.01a (1465.958 d) | |
| 45.401° | |
| Inclination | 2.342° |
| 181.168° | |
| 176.882° | |
| Physical characteristics | |
| Dimensions | 124.1 km[2] |
| Mass | 3.5×1018 kg[3] |
Meandensity | 5.81 ± 0.87[4] g/cm3 |
| 21.04[5] h | |
| 0.052[2] | |
| C | |
| 8.36[2] | |
46 Hestia is a large, darkmain-beltasteroid. It is also the primary body of theHestia clump, a group of asteroids with similar orbits.
Hestia was discovered byN. R. Pogson on August 16, 1857, at theRadcliffe Observatory,Oxford. Pogson awarded the honour of naming it toWilliam Henry Smyth, the previous owner of the telescope used for the discovery. Smyth chose to name it afterHestia,Greek goddess of thehearth.[6] This created a problem inGreek, where4 Vesta also goes by the nameHestia.
The computedLyapunov time for this asteroid is 30,000 years, indicating that it occupies a chaotic orbit that will change randomly over time because ofgravitational perturbations of the planets.[7]
Hestia has been studied byradar.[8] 13-cm radar observations of this asteroid from theArecibo Observatory between 1980 and 1985 were used to produce a diameter estimate of 131 km.[9] In 1988 a search for satellites or dust orbiting this asteroid was performed using theUH88 telescope at theMauna Kea Observatories, but the effort came up empty.[10]
Photometric observations made in 2012 at the Organ Mesa Observatory inLas Cruces, New Mexico produced alight curve with a period of 21.040 ± 0.001 hours. There are two brightness minima, having luminosity variations of 0.05 and 0.12 inmagnitude, respectively.[5]
In 2000, Michalak estimated Hestia to have a mass of 3.5×1018 kg.[3][11]
Even though Hestia is only about 124 km in diameter,[2] in 1997, Bange and Bec-Borsenberger estimated Hestia as having a mass of 2.1×1019 kg, based on aperturbation by19 Fortuna.[12][13][14] This older 1997 estimate would give it a density of 14+ g/cm3[12] and make Hestia more massive than several much larger asteroids.
