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Asteroid Lightcurve Parameters
C.-I. Lagerkvist A.W. Harris V. Zappala
Astronomiska Observatoriet JPL 183-501 Oss. Astron. di Torino
Box 515 4800 Oak Grove Dr. 10025 Pino Torinese
S-751 20 Uppsala Pasadena, CA 91109 Italy
Sweden USA
The lightcurve data file consists of three parts: the asteroid
list, the reference list, and this explanation, which includes a list of
footnotes at the end. The reference list is numbered and sorted by
first author plus date. Each citation includes the year, all authors,
journal or book name, volume, and first and last page numbers.
The asteroid list is ordered by asteroid number, followed by the
asteroid name, the period in hours, amplitude of variation or range of
amplitude observed, and a reliability code as follows:
1 Very tentitive result, may be completely wrong.
2 Reasonably secure result, based on over half coverage of the lightcurve.
3 Secure result, full lightcurve coverage, no ambiguity of period.
4 Multiple apparition coverage, pole position reported.
Following the reliability code is a space for remarks, with the
following meanings:
3 Number of extrema per rotation cycle (e.g., 1, 3). Unless otherwise
noted, two per cycle is assumed.
A Ambiguous period. The "most likely" period is listed, with other
possibilities listed in a footnote ordered by asteroid number, below.
D Rotation period "determined" from published data, but not given by
author(s) of original data.
F Footnote, below, ordered by asteroid number, containing additional
information.
N No lightcurve published.
P Photographic photometry.
V Visual photometry.
Following the remarks columns, all references to the asteroid are
cited, by number from the reference list, in chronological order. That
is, the last few citations are the most recent, and should therefore be
the most useful for evaluating the current state of knowledge of a given
asteroid.
FOOTNOTES AND ALTERNATE VALUES FOR AMBIGUOUS PERIODS
4 Degewij and Zellner (1978) and Degewij et al. (1979) show that
variation is primarily due to albedo and not due to shape. Taylor
(1985) found no asymmetry in the 10 hr lightcurve as claimed by
Taylor (1973) when he reobserved at similar aspect. Magnusson (1986)
obtains a better solution for the pole position of Vesta with a
5 hour period than with a 10 hour period.
9 Correct period is 5.079 hrs. Other values resulted from cycle
errors in compositing lightcurves.
26 P = 10.60 or 13.13 hours.
56 P = 13.7 or 19.0 hours.
139 P = 20.9 or 41.8 hours.
249 P = 42.62 or 85.24 hours.
288 Period may be a precession period (see 1220 footnote).
372 P = 6.58, 8.67, or 12.83 hours.
387 P = 16.0, 24.0, or 48.0 hours.
393 P = 19.35 or 38.7 hours.
439 P = 19.2 or 38.4 hours.
683 P = 4.3, 5.3, or 8.6 hours.
704 Pole position inferred from YANG 65 observation.
804 P = 7.42 or 14.851 hours.
944 Accurate period quoted by Tedesco (in Asteroids, ed. T. Gehrels,
Tucson: Univ. Ariz. Press, pp 1098-1107.)
1220 A modulation of P=7.90 hr, Ampl=0.15 mag was observed near minimum
light of the longer period variation. BINZEL 84B interprets this
as the real rotation period, with the long period being a preces-
sion period caused by an unseen satellite. 288 Glauke may be
another case of the same phenomenon.
3552 P = 3 or 7 hours.