6229 Tursachan

6229 Tursachan, provisional designation 1983 VN₇, is a Themistian asteroid from the outer regions of the asteroid belt, approximately 10 kilometers (6 miles) in diameter. It was discovered on 4 November 1983, by American astronomer Brian Skiff at Lowell's Anderson Mesa Station near Flagstaff, Arizona, in the United States.^[1] The presumed C-type asteroid has a rotation period of 16.6 hours and is possibly elongated.^[4] It was named after a Gaelic word meaning "Standing Stones".^[1]

6229 Tursachan

Discovery[1]
Discovered by	B. A. Skiff
Discovery site	Anderson Mesa Stn.
Discovery date	4 November 1983
Designations
MPC designation	(6229) Tursachan
Named after	"Standing Stones"[1] (Gaelic language)
Alternative designations	1983 VN7 · 1988 RC2
Minor planet category	main-belt[1][2] · (outer) Themis[3][4]
Orbital characteristics[2]
Epoch 23 March 2018 (JD 2458200.5)
Uncertainty parameter 0
Observation arc	34.40 yr (12,565 d)
Aphelion	3.6472 AU
Perihelion	2.5155 AU
Semi-major axis	3.0814 AU
Eccentricity	0.1836
Orbital period (sidereal)	5.41 yr (1,976 d)
Mean anomaly	142.06°
Mean motion	0° 10m 55.92s / day
Inclination	1.6495°
Longitude of ascending node	146.28°
Argument of perihelion	234.29°
Physical characteristics
Mean diameter	8.61 km (calculated)[4] 10.34±2.69 km[5] 11.18±3.50 km[6] 11.603±0.070 km[7][8]
Synodic rotation period	16.596±0.0167 h[9]
Geometric albedo	0.07±0.04[5] 0.076±0.012[7][8] 0.089±0.113[6] 0.08 (assumed)[4]
Spectral type	C (assumed)[4]
Absolute magnitude (H)	13.00[6][8] 13.2[2] 13.236±0.003 (R)[9] 13.39±0.24[10] 13.44[5] 13.69[4]

Orbit and classification

Tursachan is a Themistian asteroid that belongs to the Themis family (602),^[3] a very large family of carbonaceous asteroids, named after 24 Themis.^{[4][11]: 23}

It orbits the Sun in the outer main-belt at a distance of 2.5–3.6 AU once every 5 years and 5 months (1,976 days; semi-major axis of 3.08 AU). Its orbit has an eccentricity of 0.18 and an inclination of 2° with respect to the ecliptic.^[2] The body's observation arc begins with a precovery taken at Palomar Observatory just 5 nights prior to its official discovery observation at Anderson Mesa.^[1]

Physical characteristics

Tursachan is an assumed C-type asteroid,^[4] which agrees with the overall spectral type for members of the Themis family.^[11]: 23

Rotation period

In September 2010, a rotational lightcurve of Tursachan was obtained from photometric observations in the R-band by astronomers at the Palomar Transient Factory in California. Lightcurve analysis gave a rotation period of 16.596 hours with a brightness amplitude of 0.57 magnitude, indicative of an elongated shape (U=2).^[4][9]

Diameter and albedo

According to the survey carried out by the NEOWISE mission of NASA's Wide-field Infrared Survey Explorer, Tursachan measures between 10.34 and 11.603 kilometers in diameter and its surface has an albedo between 0.07 and 0.089.^[5][6][7][8]

The Collaborative Asteroid Lightcurve Link assumes an albedo of 0.08 and calculates a diameter of 8.61 kilometers based on an absolute magnitude of 13.69.^[4]

Naming

This minor planet was named after the term "Tursachan", which means "Standing Stones" in the Gaelic language, and refers to the stones often placed in circles during the Neolithic (approximately 10,000 BC to 2000 BC) on the British Isles. These stones may have been used to follow the seasons and mark astronomical events.^[1] The official naming citation was published by the Minor Planet Center on 11 February 1998 (M.P.C. 31296).^[12]