(38063) 1999 FH

(38063) 1999 FH is a rare-type asteroid from the inner regions of the asteroid belt, classified as Mars-crosser and exceptionally slow rotator, approximately 4 kilometers in diameter. It was discovered on 16 March 1999, by Croatian astronomers Korado Korlević and Mario Jurić at Višnjan Observatory in Croatia.^[2]

(38063) 1999 FH

Discovery[1]
Discovered by	K. Korlević M. Jurić
Discovery site	Višnjan Obs.
Discovery date	16 March 1999
Designations
MPC designation	(38063) 1999 FH
Alternative designations	1999 FH · 2000 SY275
Minor planet category	Mars-crosser[1][2][3]
Orbital characteristics[1]
Epoch 4 September 2017 (JD 2458000.5)
Uncertainty parameter 0
Observation arc	25.07 yr (9,158 days)
Aphelion	3.0288 AU
Perihelion	1.6559 AU
Semi-major axis	2.3424 AU
Eccentricity	0.2931
Orbital period (sidereal)	3.59 yr (1,309 days)
Mean anomaly	324.91°
Mean motion	0° 16m 29.64s / day
Inclination	11.880°
Longitude of ascending node	193.25°
Argument of perihelion	108.31°
Physical characteristics
Dimensions	3.395±0.703 km[4] 3.92 km (calculated)[3] 4.17±0.42 km[5]
Synodic rotation period	990±50 h[6][a]
Geometric albedo	0.176±0.035[5] 0.20 (assumed)[3] 0.287±0.172[4]
Spectral type	L[7] · S[3]
Absolute magnitude (H)	14.00[7] · 14.4[1][3][4][5] · 14.50±0.13[8]

Orbit and classification

1999 FH orbits the Sun at a distance of 1.7–3.0 AU once every 3 years and 7 months (1,309 days). Its orbit has an eccentricity of 0.29 and an inclination of 12° with respect to the ecliptic.^[1] A first precovery was taken at Steward Observatory in 1992, extending the body's observation arc by 7 years prior to its official discovery observation.^[2]

Physical characteristics

SDSS photometry characterized 1999 FH as a rare and reddish L-type, which belong to the larger complex of stony asteroids.^[7]

Slow rotator and tumbler

In September 2014, American astronomer Robert Stephens obtained a rotational lightcurve from photometric observations taken at the Center for Solar System Studies (CS3, U81) in California.^[a] It gave an exceptionally long rotation period of 990±50 hours with a brightness amplitude of 0.55 magnitude (U=2), which makes it one of the slowest rotators known to exist. It is also a suspected tumbling asteroid, which show a non-principal axis rotation.^[6]

Diameter and albedo

According to the survey carried out by NASA's Wide-field Infrared Survey Explorer with its subsequent NEOWISE mission, 1999 FH measures 3.395 and 4.17 kilometers in diameter and its surface has an albedo of 0.287 and 0.176, respectively.^[4] The Collaborative Asteroid Lightcurve Link assumes a standard albedo for stony asteroids of 0.20 and calculates a diameter of 3.92 kilometers with an absolute magnitude of 14.4.^[3]

Numbering and naming

This minor planet was numbered by the Minor Planet Center on 28 March 2002.^[9] As of 2018, it has not been named.^[2]

Notes

1. Robert Stephens light-curve plot of (38063) with a rotation period 990±50 hours and a brightness amplitude of 0.55 mag