|Discovered by||Johann Palisa|
|Discovery date||25 October 1888|
|1927 EC, 1954 FF, A920 GA, A923 RA|
|Asteroid belt (Thule)|
|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)|
|9.07 yr (3313.0 d)|
|0° 6m 31.184s / day|
|Dimensions||126.59±3.7 km (IRAS)|
|23.896 h (0.9957 d)|
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.
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. 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)|
|(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|
- "279 Thule". JPL Small-Body Database. NASA/Jet Propulsion Laboratory. Retrieved 11 May 2016.
- "Thule". Oxford English Dictionary (Online ed.). Oxford University Press. (Subscription or participating institution membership required.)
- "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.
- 279 Thule at AstDyS-2, Asteroids—Dynamic Site
- 279 Thule at the JPL Small-Body Database