762 Pulcova

762 Pulcova is a main-belt asteroid. It was discovered by Grigoriy N. Neujmin in 1913,^[2] and is named after Pulkovo Observatory, near Saint Petersburg. Pulcova is 137 km in diameter,^[2] and is a C-type asteroid, which means that it is dark in colouring with a carbonate composition.

762 Pulcova

762 Pulcova and satellite as seen with adaptive optics in 2000[1]
Discovery[2]
Discovered by	G. N. Neujmin
Discovery date	3 September 1913
Designations
MPC designation	(762) Pulcova
Pronunciation	/ˈpʊlkəvə/
Named after	Pulkovo Heights
Alternative designations	1913 SQ
Minor planet category	Main belt
Adjectives	Pulcovian /pʊlˈkoʊviən/[3]
Orbital characteristics[2]
Epoch 31 July 2016 (JD 2457600.5)
Uncertainty parameter 0
Observation arc	100.08 yr (36553 d)
Aphelion	3.4801 AU (520.62 Gm) (Q)
Perihelion	2.8291 AU (423.23 Gm) (q)
Semi-major axis	3.1546 AU (471.92 Gm) (a)
Eccentricity	0.10319 (e)
Orbital period (sidereal)	5.60 yr (2046.5 d)
Mean anomaly	348.62° (M)
Mean motion	0° 10m 33.276s / day (n)
Inclination	13.089° (i)
Longitude of ascending node	305.76° (Ω)
Argument of perihelion	189.54° (ω)
Known satellites	S/2000 (762) 1[1]
Earth MOID	1.84297 AU (275.704 Gm)
Jupiter MOID	1.60162 AU (239.599 Gm)
TJupiter	3.158
Physical characteristics
Mean radius	68.54±1.6 km
Mass	1.40×1018 kg[4]
Mean density	0.90 g/cm3[4]
Synodic rotation period	5.839 h (0.2433 d)
Sidereal rotation period	5.839 hr[2]
Geometric albedo	0.0458±0.002[2]
Apparent magnitude	11.93 to 14.79[5]
Absolute magnitude (H)	8.28[2]

Photometric observations of this asteroid from Leura, Australia during 2006 gave a light curve with a period of 5.8403 ± 0.0005 hours and a brightness variation of 0.20 ± 0.02 in magnitude. This result is in agreement with previous studies.^[6]

Satellite

Pulcova and its satellite imaged by the Hubble Space Telescope in January 2005

Diagram of 762 Pulcova's orbit

On February 22, 2000,^[1] astronomers at the Canada-France-Hawaii Telescope on Mauna Kea, Hawaii, discovered a 15-km moon (roughly a tenth the size of the primary)^[7] orbiting Pulcova at a distance of 800 km.^[8] Its orbital period is 4 days.^[9] The satellite is about 4 magnitudes fainter than the primary.^[8] It was one of the first asteroid moons to be identified.

Density

In the year 2000, Merline estimated Pulcova to have a density of 1.8 g/cm³, which would make it more dense than the triple asteroid 45 Eugenia, and binary 90 Antiope.^[8] But estimates by Marchis in 2008 suggest a density of only 0.90 g/cm³,^[4] suggesting it may be a loosely packed rubble pile, not a monolithic object.