1156 Kira

1156 Kira, provisional designation 1928 DA, is a stony background asteroid from the inner regions of the asteroid belt, approximately 9 kilometers in diameter. It was discovered on 22 February 1928, by German astronomer Karl Reinmuth at Heidelberg Observatory in southwest Germany.^[13] Any reference of its name to a person or occurrence is unknown.^[2]

1156 Kira

Discovery[1]
Discovered by	K. Reinmuth
Discovery site	Heidelberg Obs.
Discovery date	22 February 1928
Designations
MPC designation	(1156) Kira
Named after	unknown[2]
Alternative designations	1928 DA · 1935 FY 1938 DA · 1953 RC1 1955 FW1 · 1973 QC2
Minor planet category	main-belt · (inner)[3] background[4]
Orbital characteristics[1]
Epoch 4 September 2017 (JD 2458000.5)
Uncertainty parameter 0
Observation arc	88.76 yr (32,418 days)
Aphelion	2.3414 AU
Perihelion	2.1329 AU
Semi-major axis	2.2372 AU
Eccentricity	0.0466
Orbital period (sidereal)	3.35 yr (1,222 days)
Mean anomaly	326.67°
Mean motion	0° 17m 40.2s / day
Inclination	1.3976°
Longitude of ascending node	91.131°
Argument of perihelion	353.76°
Physical characteristics
Dimensions	6.83±0.21 km[5] 6.831±0.211 km[5] 8.79±1.97 km[6] 8.856±0.105 km[7] 9.00±2.24 km[8] 10.30 km (calculated)[3] 10.83±0.76 km[9]
Synodic rotation period	2.7910±0.0005 h[a] 2.79103±0.00004 h[10] 2.79105±0.00003 h[10] 2.79113±0.00004 h[10]
Geometric albedo	0.165±0.024[9] 0.181±0.052[11] 0.20 (assumed)[3] 0.2490±0.0585[7] 0.26±0.14[6] 0.29±0.12[8] 0.455±0.066[5]
Spectral type	S[3]
Absolute magnitude (H)	12.30[1][3][5][8] · 12.40[7][9] · 12.48±0.35[12] · 12.72[6]

Orbit and classification

Kira is not a member of any known asteroid family and belongs to the main belt's background population.^[4] At the present epoch, however, it orbits within the region of the Flora family.^[10]

This asteroid orbits the Sun in the inner main-belt at a distance of 2.1–2.3 AU once every 3 years and 4 months (1,222 days). Its orbit has an eccentricity of 0.05 and an inclination of 1° with respect to the ecliptic.^[1] The body's observation arc begins with its official discovery observation at Heidelberg.^[13]

Physical characteristics

Kira is an assumed stony S-type asteroid.^[3]

Rotation period

Several rotational lightcurves of Kira have been obtained from photometric observations since 2007. Lightcurve analysis gave a rotation period between 2.7910 and 2.79113 hours with a brightness variation of 0.20 to 0.26 magnitude (U=3/3/3/2+).^[10][a]

Diameter and albedo

According to the surveys carried out by the Japanese Akari satellite and the NEOWISE mission of NASA's Wide-field Infrared Survey Explorer, Kira measures between 6.83 and 10.83 kilometers in diameter and its surface has an albedo between 0.165 and 0.455.^{[5][6][7][8][9][11]}

The Collaborative Asteroid Lightcurve Link assumes a standard albedo for stony asteroids of 0.20 and calculates a diameter of 10.30 kilometers based on an absolute magnitude of 12.3.^[3]

Naming

This minor planet was named by astronomer Max Mündler, staff member at Heidelberg Observatory. Any reference of its name to a person or occurrence is unknown.^[2]

Unknown meaning

Among the many thousands of named minor planets, Kira is one of 120 asteroids, for which no official naming citation has been published. All of these low-numbered asteroids have numbers between 164 Eva and 1514 Ricouxa and were discovered between 1876 and the 1930s, predominantly by astronomers Auguste Charlois, Johann Palisa, Max Wolf and Karl Reinmuth.^[14]

Notes

1. Pravec (2012), lightcurve plot of (1156) Kira. Observation: 10 April 2012. Rotation period 2.7910±0.0005 hours with a brightness amplitude of 0.20±0.02 mag. Quality Code of 3. summary figures at Ondrejov Asteroid Photometry Project. Note: figure published at the LCDB contains a typo.