The Confusing Case of 16666 Liroma
Abstract
In late 2011, asteroid 16666 Liroma made a very favorable apparition with unusually bright magnitude and passing through near-zero solar phase angle. This opportunity prompted a project to determine the rotation period, lightcurve shape, and phase curve parameters (H, G) of this asteroid. The rotation period P = 112 ± 5 h that we find, with amplitude A ~ 0.45 ± 0.05 mag (peak-to-peak) seems to be well-justified. The lightcurve gives a fair fit to almost all of the data gathered on 21 nights over an period of 2 months. However, three nights at the largest phase angle (at the end of the observed apparition) fall significantly "off" the lightcurve. An attempt to fit the lightcurve to a two-period model gives a somewhat better fit, but still leaves substantial deviations from a model lightcurve, thus presenting an unresolved mystery.
- Publication:
-
Society for Astronomical Sciences Annual Symposium
- Pub Date:
- May 2012
- Bibcode:
- 2012SASS...31..209B