Discovered by Johann Palisa Minor planet category Asteroid belt (Thule) Discovered 25 October 1888 Spectral type C-type asteroid Discoverer Johann Palisa | Discovery date 25 October 1888 Observation arc 125.34 yr (45780 d) Orbits Sun Asteroid group Asteroid belt Discovery site Vienna Observatory | |
Alternative names 1927 EC, 1954 FF, A920 GA, A923 RA Aphelion 4.4617880 AU (667.47398 Gm) Similar 153 Hilda, Asteroid belt, 375 Ursula, 423 Diotima, 276 Adelheid | ||
279 Thule (/ˈθjuːliː/ THEW-lee) is a large asteroid from the 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 October 25, 1888 in Vienna and was named aptly after the ultimate northern land of Thule.
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. 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.