4997 Ksana

4997 Ksana, provisional designation 1986 TM, is a carbonaceous Palladian asteroid from the outer region of the asteroid belt, approximately 10 kilometers in diameter. It was discovered on 6 October 1986, by Russian astronomer Lyudmila Karachkina at Crimean Astrophysical Observatory on the Crimean peninsula.^[12] The asteroid was named for Russian chemist Kseniya Nessler.^[2]

4997 Ksana

Discovery[1]
Discovered by	L. G. Karachkina
Discovery site	Crimean Astrophysical Obs.
Discovery date	6 October 1986
Designations
MPC designation	(4997) Ksana
Named after	Kseniya A. Nessler (Russian chemist)[2]
Alternative designations	1986 TM
Minor planet category	main-belt · (outer)[3] Pallas[4]
Orbital characteristics[1]
Epoch 4 September 2017 (JD 2458000.5)
Uncertainty parameter 0
Observation arc	30.57 yr (11,165 days)
Aphelion	3.8162 AU
Perihelion	1.9285 AU
Semi-major axis	2.8723 AU
Eccentricity	0.3286
Orbital period (sidereal)	4.87 yr (1,778 days)
Mean anomaly	97.646°
Mean motion	0° 12m 9s / day
Inclination	32.828°
Longitude of ascending node	10.897°
Argument of perihelion	57.447°
Physical characteristics
Dimensions	7.36±2.79 km[5] 9.860±0.160 km[6][7] 9.97±0.33 km[8] 10±1 km[9] 14.64 km (calculated)[3]
Synodic rotation period	3.4342±0.0003 h[10]
Geometric albedo	0.057 (assumed)[3] 0.16±0.03[9] 0.271±0.206[5] 0.312±0.022[8] 0.3157±0.0548[7] 0.316±0.055[6]
Spectral type	SMASS = B[1] · B[3]
Absolute magnitude (H)	11.9[3][7][8] · 12.70[5][9] · 12.79±0.30[11] · 13.0[1]

Orbit and classification

Ksana is a small member of the Pallas family (801), a small asteroid family of carbonaceous B-type asteroids.^{[4][13]: 23} It orbits the Sun in the outer main-belt at a distance of 1.9–3.8 AU once every 4 years and 10 months (1,778 days). Its orbit has an eccentricity of 0.33 and an inclination of 33° with respect to the ecliptic.^[1] As no precoveries were taken, the asteroid's observation arc begins with its discovery observation in 1986.^[12]

Physical characteristics

On the SMASS taxonomic scheme, Ksana is a B-type asteroid, which are primitive, volatile-rich asteroids.^[1] This also agrees with the overall spectral type of the Pallas family.^[13]: 23

Diameter and albedo

According to the surveys carried out by the Japanese Akari satellite and NASA's Wide-field Infrared Survey Explorer with its subsequent NEOWISE mission, Ksana measures between 7.36 and 10±1 kilometers in diameter and its surface has an albedo between 0.16 and 0.316.^{[5][6][7][8][9]}

The Collaborative Asteroid Lightcurve Link assumes a standard albedo for carbonaceous asteroids of 0.057 and calculates a larger diameter of 14.64 kilometers with an absolute magnitude of 12.9.^[3]

Rotation period

In February 2007, a rotational lightcurve of Ksana was obtained from photometric observations by Italian astronomer Federico Manzini at the SAS observatory in Novara, Italy. It gave it a rotation period of 3.4342±0.0003 hours with a brightness variation of 0.21 in magnitude (U=2).^[10]

Naming

This minor planet was named by the discoverer for his friend, the Russian chemist Kseniya Andreevna Nessler, who has been an advocate against environmental pollution. The asteroid's name "Ksana" is a variation of Kseniya (Ксения), the equivalent to the romanized Xenia.^[2] The official naming citation was published by the Minor Planet Center on 1 September 1993 (M.P.C. 22505 and 22609).^[14]