279 Thule
Thule, minor planet designation: 279 Thule, is a large asteroid from the outer asteroid belt. It is classified as a D-type asteroid and is probably composed of organic-rich silicates, carbon and anhydrous silicates. Thule was the first asteroid discovered with a semi-major axis greater than 4 AU. It was discovered by Johann Palisa on 25 October 1888 in Vienna and was named after the ultimate northern land of Thule.
| Discovery | |
|---|---|
| Discovered by | Johann Palisa | 
| Discovery date | 25 October 1888 | 
| Designations | |
| (279) Thule | |
| Pronunciation | /ˈθjuːliː/[1] | 
| 1927 EC, 1954 FF, A920 GA, A923 RA[2] | |
| Asteroid belt (Thule) | |
| Adjectives | Thulean /ˈθjuːliən/[3] | 
| Orbital characteristics[2] | |
| Epoch 31 July 2016 (JD 2457600.5) | |
| Uncertainty parameter 0 | |
| Observation arc | 125.34 yr (45780 d) | 
| Aphelion | 4.4617880 AU (667.47398 Gm) | 
| Perihelion | 4.2367660 AU (633.81117 Gm) | 
| 4.3492770 AU (650.64258 Gm) | |
| Eccentricity | 0.025869 | 
| 9.07 yr (3313.0 d) | |
| 62.75874° | |
| 0° 6m 31.184s / day | |
| Inclination | 2.323774° | 
| 72.46791° | |
| 42.36797° | |
| Physical characteristics | |
| Dimensions | 126.59±3.7 km (IRAS)[2] | 
| 23.896 h (0.9957 d)[2] | |
| 0.0412±0.003[2] | |
| Temperature | 133 K | 
| B−V=0.75[2] U−B=0.32[2] D (Tholen)[2] X (SMASSII)[2] | |
| 8.57[2] | |
Thule asteroids
    
Thule was the first discovered member of the Thule dynamical group, which as of 2008 is known to consist of three objects: 279 Thule, (186024) 2001 QG207, and (185290) 2006 UB219.[4] The orbits of these bodies are unusual. They orbit in the outermost edge of the asteroid belt in a 4:3 orbital resonance with Jupiter, the result of the periodic force Jupiter exerts on a body with Thule's orbital period, in the same way (though with the reverse effect) as the Kirkwood gaps in the more inner parts of the asteroid belt.
| Name | semimajor axis (au) | period (years) | eccentricity | inclination (°) | absolute magnitude | Size (km) | 
|---|---|---|---|---|---|---|
| 279 Thule | 4.269 | 8.82 | 0.0432 | 2.334 | 8.53 | 126.59±3.7 | 
| (185290) 2006 UB219 | 4.290 | 8.89 | 0.1335 | 7.132 | 13.84 | 4.1–10.1 | 
| (186024) 2001 QG207 | 4.278 | 8.85 | 0.2513 | 3.238 | 14.53 | 3.0–7.4 | 
| 2006 SJ42 | 4.286 | 8.87 | 0.0465 | 5.501 | 15.1 | 2.3–5.7 | 
| 2008 RE93 | 4.288 | 8.88 | 0.1161 | 3.497 | 15.49 | 1.9–4.7 | 
| 2014 WN504 | 4.297 | 8.91 | 0.2312 | 3.193 | 15.5 | 1.9–4.7 | 
| 2014 QX231 | 4.283 | 8.86 | 0.3722 | 5.935 | 16.5 | 1.2–3.0 | 
References
    
- "Thule". Oxford English Dictionary (Online ed.). Oxford University Press. (Subscription or participating institution membership required.)
- "279 Thule". JPL Small-Body Database. NASA/Jet Propulsion Laboratory. Retrieved 11 May 2016.
- "Thulean". Oxford English Dictionary (Online ed.). Oxford University Press. (Subscription or participating institution membership required.)
- Brož, M.; Vokrouhlický, D. (2008). "Asteroid families in the first-order resonances with Jupiter". Monthly Notices of the Royal Astronomical Society. 390 (2): 715–732. arXiv:1104.4004. Bibcode:2008MNRAS.390..715B. doi:10.1111/j.1365-2966.2008.13764.x. S2CID 53965791.
External links
    
- 279 Thule at AstDyS-2, Asteroids—Dynamic Site
- 279 Thule at the JPL Small-Body Database