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 as follows: Bytes: Field: 1-4 Asteroid number 6-19 Asteroid name 20 a '>' may be located in this column associated with the period in the next field 21-27 period in hours (F7.3) 30-33, 34-38 Amplitude of variation or Range of amplitude observed. (F4.2, F5.2). Byte 34 may contain a character associated with the second measurement. 40 Reliability code The Reliability Codes are 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. 43-44 Remark codes The Remarks Codes are as follows: 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. 51-77 Reference codes: (I3,1X,I3,1X,I3,1X,..etc.) All references to the asteroid are cited by number in the reference file, in chronological order. The last few citations are the most recent, and should 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-hour 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.