The bimodal color distribution of small Kuiper Belt objects

Abstract

We conducted a two-night photometric survey of small Kuiper Belt objects (KBOs) near opposition using the wide-field Hyper Suprime-Cam instrument on the 8.2 m Subaru Telescope. The survey covered about 90 deg^2 of sky, with each field imaged in the g and i bands. We detected 356 KBOs, ranging in absolute magnitude from 6.5 to 10.4. Filtering for high-inclination objects within the hot KBO population, we show that the g-i color distribution is strongly bimodal, indicative of two color classes - the red and very red subpopulations. After categorizing objects into the two subpopulations by color, we present the first dedicated analysis of the magnitude distributions of the individual color subpopulations and demonstrate that the two distributions are roughly identical in shape throughout the entire size range covered by our survey. Comparing the color distribution of small hot KBOs with that of Centaurs, we find that they have similar bimodal shapes, thereby providing strong confirmation of previous explanations for the attested bimodality of Centaurs. We also show that the magnitude distributions of the two KBO color subpopulations and the two color subpopulations observed in the Jupiter Trojans are statistically indistinguishable. Finally, we discuss a hypothesis describing the origin of the KBO color bimodality based on our survey results.

arXiv comment9 pages, 6 figures, accepted for publication in AJ, supplemental table accessible on online journal

References in corpus (19)

• Origin of the Structure of the Kuiper Belt during a Dynamical Instability in the Orbits of Uranus and Neptune
• Solar System Objects Observed in the SDSS Commissioning Data
• The Size Distribution of Trans-Neptunian Bodies
• The Absolute Magnitude Distribution of Kuiper Belt Objects
• Orbit Fitting and Uncertainties for Kuiper Belt Objects
• The Compositions of Kuiper Belt Objects
• The Hubble Wide Field Camera 3 Test of Surfaces in the Outer Solar System: The Compositional Classes of the Kuiper Belt
• The albedo-color diversity of transneptunian objects
• Reopening the TNOs Color Controversy: Centaurs Bimodality and TNOs Unimodality
• Colors and taxonomy of Centaurs and Trans-Neptunian Objects
• Colours of minor bodies in the outer solar system - II: A statistical analysis revisited
• The Bimodal Colors of Centaurs and Small Kuiper Belt Objects
• A hypothesis for the color bimodality of Jupiter Trojans
• Taxonomy of asteroid families among the Jupiter Trojans: Comparison between spectroscopic data and the Sloan Digital Sky Survey colors
• Reanalyzing the visible colors of Centaurs and KBOs: what is there and what we might be missing
• The Color Differences of Kuiper Belt Objects in Resonance with Neptune
• The differing magnitude distributions of the two Jupiter Trojan color populations
• The color-magnitude distribution of small Jupiter Trojans
• OSSOS II: A Sharp Transition in the Absolute Magnitude Distribution of the Kuiper Belt's Scattering Population

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