Photometric measurements during 2009 produced a lightcurve that indicated a sidereal rotation period of 19.489±0.002 h with a variation amplitude of 0.18±0.02 magnitudes. This result conflicted with previous determinations of the period, so the latter were ruled out.[4]
References
^Noah Webster (1884) A Practical Dictionary of the English Language
^ abPilcher, Frederick (January 2010), "Rotational Period Determination for 23 Thalia, 204 Kallisto and 207 Hedda, and Notes on 161 Athor and 215", The Minor Planet Bulletin, 37 (1): 21−23, Bibcode:2010MPBu...37...21P.
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