Astronomy:762 Pulcova

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762 Pulcova
762Pulcova-SwRI.gif
762 Pulcova and satellite as seen with adaptive optics in 2000[1]
Discovery[2]
Discovered byG. N. Neujmin
Discovery date3 September 1913
Designations
(762) Pulcova
Pronunciation/ˈpʊlkəvə/
Named afterPulkovo Heights
1913 SQ
Minor planet categoryMain belt
AdjectivesPulcovian /pʊlˈkviən/[3]
Orbital characteristics[2]
Epoch 31 July 2016 (JD 2457600.5)
Uncertainty parameter 0
Observation arc100.08 yr (36553 d)
|{{{apsis}}}|helion}}3.4801 astronomical unit|AU (520.62 Gm) (Q)
|{{{apsis}}}|helion}}2.8291 AU (423.23 Gm) (q)
3.1546 AU (471.92 Gm) (a)
Eccentricity0.10319 (e)
Orbital period5.60 yr (2046.5 d)
Mean anomaly348.62° (M)
Mean motion0° 10m 33.276s / day (n)
Inclination13.089° (i)
Longitude of ascending node305.76° (Ω)
189.54° (ω)
Known satellitesS/2000 (762) 1[1]
Earth MOID1.84297 AU (275.704 Gm)
Jupiter MOID1.60162 AU (239.599 Gm)
TJupiter3.158
Physical characteristics
Mean radius68.54±1.6 km
Mass1.40×1018 kg[4]
Mean density0.90 g/cm3[4]
Rotation period5.839 h (0.2433 d)
Sidereal rotation period5.839 hr[2]
Geometric albedo0.0458±0.002[2]
Apparent magnitude11.93 to 14.79[5]
Absolute magnitude (H)8.28[2]


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.

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 trinary 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.

References

  1. Jump up to: 1.0 1.1 1.2 "762 Pulcova". SwRI. 2000-02-22. http://www.boulder.swri.edu/merline/press/fig3.html.  (AO image)
  2. Jump up to: 2.0 2.1 2.2 2.3 2.4 2.5 2.6 "JPL Small-Body Database Browser: 762 Pulcova (1913 SQ)". https://ssd.jpl.nasa.gov/sbdb.cgi?sstr=762. 
  3. Catalogue of the Mathematical, Historical, Bibliographical and Miscellaneous Portion of the Celebrated Library of M. Guglielmo Libri, 1861, p. 216
  4. Jump up to: 4.0 4.1 4.2 Jim Baer (2008). "Recent Asteroid Mass Determinations". Personal Website. http://home.earthlink.net/~jimbaer1/astmass.txt. 
  5. Magnitudes generated with JPL Horizons for the year 1950 through 2100
  6. Oey, Julian (December 2006), "Lightcurves analysis of 10 asteroids from Leura Observatory", The Minor Planet Bulletin 33 (4): 96–99, Bibcode2006MPBu...33...96O. 
  7. Dr. William J. Merline; Maria Martinez (2000-10-26). "Astronomers Image Double Asteroid". SwRI Press Release. http://www.boulder.swri.edu/merline/press/release.txt.  (mentions both 90 Antiope and 762 Pulcova)
  8. Jump up to: 8.0 8.1 8.2 W.J. Merline (SwRI); L.M. Close (ESO, U. Arizona) (2000-06-21). "Discovery of Companions to Asteroids 762 Pulcova and 90 Antiope by Direct Imaging". SwRI. http://www.boulder.swri.edu/merline/press/dps.abstract.pdf. 
  9. Johnston, Robert (September 1, 2005). "(762) Pulcova". Johnston's Archive. http://www.johnstonsarchive.net/astro/astmoons/am-00762.html. 

External links