[en] Photoelectric lightcurves of 532 Herculina in 1984 show two maxima and two minima with a synodic rotation period of 0.39185±0.00002 day (1sigma). During some other oppositions the Herculina lightcurve has only one maximum and one minimum over that same rotation period. The absolute magnitude in V is 6.13±0.02 mag, the phase coefficient in V is 0.037±0.002, and the mean colors are B-V = +0.86±0.04 and U-B = +0.43±0.02. The authors applied photometric astrometry and the results indicate a sidereal period of 0.3918711±0.0000001 day with retrograde rotation for a north pole at 276° long and +1° lat. The uncertainty of the pole is ±1°. A model of Herculina is presented that generates lightcurves consistent with both the observed amplitudes and the timings of extrema over precisely 28,630 sidereal rotations during 30 years.
Disciplines :
Space science, astronomy & astrophysics
Author, co-author :
Taylor, R. C.; Arizona, University, Tucson, AZ
Birch, P. V.; Perth Observatory, Bickley, Australia
Drummond, J.; Steward Observatory, Tucson, AZ
Pospieszalska-Surdej, Anna ; Université de Liège - ULiège > Département d'astrophys., géophysique et océanographie (AGO) > Astroph. extragalactique et observations spatiales (AEOS)
Surdej, Jean ; Université de Liège - ULiège > Département d'astrophys., géophysique et océanographie (AGO) > Astroph. extragalactique et observations spatiales (AEOS)
Language :
English
Title :
Asteroid 532 Herculina - Lightcurves, pole orientation and a model
Publication date :
February 1987
Journal title :
Icarus
ISSN :
0019-1035
eISSN :
1090-2643
Publisher :
Academic Press, San Diego, United States - California
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