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arXiv · 0711.2288

Detection of Contact Binaries Using Sparse High Phase Angle Lightcurves

Pedro Lacerda
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Abstract

We show that candidate contact binary asteroids can be efficiently identified from sparsely sampled photometry taken at phase angles >60deg. At high phase angle, close/contact binary systems produce distinctive lightcurves that spend most of the time at maximum or minimum (typically >1mag apart) brightness with relatively fast transitions between the two. This means that a few (~5) sparse observations will suffice to measure the large range of variation and identify candidate contact binary systems. This finding can be used in the context of all-sky surveys to constrain the fraction of contact binary near-Earth objects. High phase angle lightcurve data can also reveal the absolute sense of the spin.

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Pedro Lacerda. 2007-11-14. Detection of Contact Binaries Using Sparse High Phase Angle Lightcurves. https://doi.org/10.1086/526454

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