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تسجيل مستخدم جديدFraction of Contact Binary Trojan Asteroids
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We present the results of an optical lightcurve survey of 114 Jovian Trojan asteroids conducted to determine the fraction of contact binaries. Sparse-sampling was used to assess the photometric range of the asteroids and those showing the largest ranges were targeted for detailed follow-up observations. This survey led to the discovery of two Trojan asteroids, (17365) and (29314) displaying large lightcurve ranges (~1 magnitude) and long rotation periods (< 2 rotations per day consistent with a contact binary nature. The optical lightcurves of both asteroids are well matched by Roche binary equilibrium models. Using these binary models, we find low densities of ~600 kg/m^3 and 800 kg/m^3, suggestive of porous interiors. The fraction of contact binaries is estimated to be between 6% and 10%, comparable to the fraction in the Kuiper Belt. The total binary fraction in the Trojan clouds (including both wide and close pairs) must be higher.
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The Trojan asteroids provide a unique perspective on the history of Solar System. As a large population of small bodies, they record important gravitational interactions and dynamical evolution of the Solar System. In the past decade, significant adv
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All the Trojan asteroids orbit about the Sun at roughly the same heliocentric distance as Jupiter. Differences in the observed visible reflection spectra range from neutral to red, with no ultra-red objects found so far. Given that the Trojan asteroi
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We observed the Mars Trojan asteroids (5261) Eureka and (101429) 1998 VF31 and the candidate Mars Trojan 2001 FR127 at 11.2 and 18.1 microns using Michelle on the Gemini North telescope. We derive diameters of 1.28, 0.78, and <0.52 km, respectively,
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