.png) A three-dimensional model of 76 Freia based on its light curve. | |
| Discovery | |
|---|---|
| Discovered by | Heinrich d'Arrest |
| Discovery date | October 21, 1862 |
| Designations | |
| (76) Freia | |
| Pronunciation | /ˈfreɪ.ə/[1] |
Named after | Freyja |
| Outer main belt[2] (Cybele) | |
| Adjectives | Freian |
| Orbital characteristics | |
| Epoch December 31, 2006 (JD 2454100.5) | |
| Aphelion | 594.715 Gm (3.975 AU) |
| Perihelion | 427.898 Gm (2.860 AU) |
| 511.306 Gm (3.418 AU) | |
| Eccentricity | 0.163 |
| 2307.979 d (6.32 a) | |
Average orbital speed | 16.00 km/s |
| 299.268° | |
| Inclination | 2.116° |
| 204.535° | |
| 254.070° | |
| Physical characteristics | |
| Dimensions | 183.7±4 km[2] |
| Mass | (1.97 ± 4.20) × 1018 kg[3] |
Mean density | 0.79 ± 1.69[3] g/cm3 |
Equatorial surface gravity | 0.0513 m/s2 |
Equatorial escape velocity | 0.0971 km/s |
| 9.968240±0.000009 h[4] | |
| 0.036 [5] | |
| CP | |
| 7.90 | |
76 Freia is a very large main-belt asteroid. It orbits in the outer part of the asteroid belt and is classified as a Cybele asteroid.[6] Its composition is very primitive and it is extremely dark in color. Freia was discovered by the astronomer Heinrich d'Arrest on October 21, 1862, in Copenhagen, Denmark. It was his first and only asteroid discovery. It is named after the goddess Freyja in Norse mythology.
The sidereal orbital period of this asteroid is commensurable with that of Jupiter, which made it useful for ground-based mass estimates of the giant planet.[7] A shape model for the asteroid was published by Stephens and Warner (2008), based upon lightcurve data. This yielded a sidereal rotation period of 9.968240±0.000009 h. They found two possible solutions for the spin axis, with the preferred solution in ecliptic coordinates being (λ, β) = (139°±5°, 25°±5°).[4]
- ^ "Freya". Lexico UK English Dictionary. Oxford University Press. Archived from the original on 22 March 2020.
- ^ a b "JPL Small-Body Database Browser: 76 Freia" (2008-03-04 last obs). Retrieved 5 September 2010.
- ^ a b Cite error: The named reference
Carry2012was invoked but never defined (see the help page). - ^ a b Cite error: The named reference
Stephens2008was invoked but never defined (see the help page). - ^ Asteroid Data Sets Archived 2009-12-17 at the Wayback Machine
- ^ Cite error: The named reference
De_Prá_et_al_2018was invoked but never defined (see the help page). - ^ Cite error: The named reference
Klepczynski1971was invoked but never defined (see the help page).