5040 Rabinowitz

5040 Rabinowitz, provisional designation 1972 RF, is a stony Phocaea asteroid from the inner regions of the asteroid belt, approximately 6 kilometers in diameter. It was discovered by Dutch–American astronomer Tom Gehrels at Palomar Observatory on 15 September 1972.^[8] Contrary to most of his discoveries, this asteroid is unrelated to the Palomar–Leiden survey and exclusively credited to Tom Gehrels.

5040 Rabinowitz

Discovery[1]
Discovered by	T. Gehrels
Discovery site	Palomar Obs.
Discovery date	15 September 1972
Designations
MPC designation	(5040) Rabinowitz
Named after	David Rabinowitz (American astronomer)[2]
Alternative designations	1972 RF · 1987 QE
Minor planet category	main-belt · Phocaea[3][4]
Orbital characteristics[1]
Epoch 4 September 2017 (JD 2458000.5)
Uncertainty parameter 0
Observation arc	46.20 yr (16,874 days)
Aphelion	2.9644 AU
Perihelion	1.8705 AU
Semi-major axis	2.4174 AU
Eccentricity	0.2263
Orbital period (sidereal)	3.76 yr (1,373 days)
Mean anomaly	7.0892°
Mean motion	0° 15m 43.92s / day
Inclination	24.361°
Longitude of ascending node	175.69°
Argument of perihelion	149.71°
Physical characteristics
Dimensions	6.41 km (calculated)[3]
Synodic rotation period	4.472±0.001 h[5] 4.6901±0.0004 h[a] 4.691±0.001 h[6]
Geometric albedo	0.23 (assumed)[3]
Spectral type	S[3]
Absolute magnitude (H)	12.73±0.13 (R)[a] · 12.9[1] · 13.15±0.35[7] · 13.18[3]

Orbit and classification

The stony S-type asteroid is a member of the Phocaea family (701), a group of asteroids with similar orbital characteristics, named after its largest member, 25 Phocaea.^[4] It orbits the Sun in the inner main-belt at a distance of 1.9–3.0 AU once every 3 years and 9 months (1,373 days). Its orbit has an eccentricity of 0.23 and an inclination of 24° with respect to the ecliptic.^[1] A first precovery was taken at the discovering observatory in 1971, extending the body's observation arc by one year prior to its official discovery observation.^[8]

Physical characteristics

Rotation period

In July 2013, a rotational lightcurve for this asteroid was obtained from photometric observations by Czech astronomer Petr Pravec at the Ondřejov Observatory. The well-defined lightcurve gave a rotation period of 4.6901±0.0004 hours with a brightness variation of 0.33 in magnitude (U=3).^[a]

During the same opposition opportunity, two more lightcurves – obtained by Robert Stephens at the Center for Solar System Studies and by Maurice Clark at the Preston Gott Observatory – gave a similar period of 4.691 and 4.472 hours, with an amplitude of 0.35 and 0.31 in magnitude, respectively (U=3-/2+).^[5][6]

Diameter and albedo

The Collaborative Asteroid Lightcurve Link assumes an albedo of 0.23, derived from the Phocaea family's namesake, and calculates a diameter of 6.4 kilometers with an absolute magnitude of 13.18.^[3]

Naming

This minor planet was named after American astronomer David Rabinowitz (born 1960), a discoverer of minor planets himself and researcher at Yale University. The naming also honors his work for the Spacewatch program.^[2] The official naming citation was published by the Minor Planet Center on 1 September 1993 (M.P.C. 22505).^[9]

Notes

1. Pravec (2013): lightcurve plot of (5040) Rabinowitz with a rotation period 4.6901±0.0004 hours with a brightness amplitude of 0.33 mag and an abs. magnitude of 12.73. Summary figures at Collaborative Asteroid Lightcurve Link (CALL) and Pravec, P.; Wolf, M.; Sarounova, L. (2013)