2025/07/01 by Anicia Arredondo · 1 voice
Earth and Planetary Sciences · Physics and Astronomy · #Astro and Planetary Science #High-pressure geophysics and materials #Stellar, planetary, and galactic studies
paper · doi:10.3847/psj/ade67a
openalex publication_date 2025/07/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/05/21
Abstract The Eurybates family is the largest collisional family in the Jupiter Trojan population. Previous visible spectroscopy of asteroid (3548) Eurybates has shown potential surface heterogeneity due to rotation of the asteroid. New near-infrared (NIR; 0.7–2.52 μ m) spectra of the three largest family members, (3548) Eurybates, (8060) Anius, and (18060) Zarex, were obtained with the NASA Infrared Telescope Facility. At least two spectra of each object were obtained, at different points of their respective rotational periods, to assess if they were compositionally heterogeneous as suggested by visible spectroscopy of (3548) Eurybates. The spectral slope, <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:msup> <mml:mrow> <mml:mi>S</mml:mi> </mml:mrow> <mml:mrow> <mml:mo accent="true">′</mml:mo> </mml:mrow> </mml:msup> </mml:math> , between 0.95 and 2.30 μ m was computed for each spectrum, and the <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:msup> <mml:mrow> <mml:mi>S</mml:mi> </mml:mrow> <mml:mrow> <mml:mo accent="true">′</mml:mo> </mml:mrow> </mml:msup> </mml:math> for each observation was compared to the average spectrum of each object to look for significant deviation from the mean. No evidence of rotational heterogeneity was found in the NIR on any of the three objects. Additionally, (8060) Anius is classified as a C type based on visible and NIR spectroscopy. The lack of rotational variability in the NIR suggests that the Eurybates family formed from the breakup of an undifferentiated asteroid. Future observations by the NASA Lucy mission will provide high-resolution and rotationally resolved spectra of (3548) Eurybates, allowing for a ground-truth assessment of heterogeneity on the surface.