Basalt or not? Near-infrared spectra, surface mineralogical estimates, and meteorite analogs for 33 Vp-type asteroids

Abstract

Investigations of the main asteroid belt and efforts to constrain that population's physical characteristics involve the daunting task of studying hundreds of thousands of small bodies. Taxonomic systems are routinely employed to study the large scale nature of the asteroid belt because they utilize common observational parameters, but asteroid taxonomies only define broadly observable properties and are not compositionally diagnostic (Tholen, 1984; Carvano et al., 2010, Hasselmann et al., 2012). This work builds upon the results of Hardersen et al. (2014, 2015), which has the goal of constraining the abundance and distribution of basaltic asteroids throughout the main asteroid belt. We report on the near infrared (NIR: 0.7 to 2.5 microns) reflectance spectra, surface mineralogical characterizations, spectral band parameter analysis, and meteorite analogs for 33 Vp asteroids. NIR reflectance spectroscopy is an effective remote sensing technique to detect most pyroxene group minerals, which are spectrally distinct with two very broad spectral absorptions at 0.9 and 1.9 microns (Cloutis et al., 1986; Gaffey et al., 2002; Burbine et al., 2009). Combined with the results from Hardersen et al. (2014, 2015), we identify basaltic asteroids for 95 percent (39 of 41) of our inner-belt Vp sample, but only 25 percent (2 of 8) of the outer-belt Vp sample. Inner belt basaltic asteroids are most likely associated with 4 Vesta and represent impact fragments ejected from previous collisions. Outer belt Vp asteroids exhibit disparate spectral, mineralogic, and meteorite analog characteristics and likely originate from diverse parent bodies. The discovery of two additional likely basaltic asteroids provides additional evidence for an outer-belt basaltic asteroid population.

arXiv comment32 pages, 5 figures, 4 tables

References in corpus (13)

• The Fourth Data Release of the Sloan Digital Sky Survey
• Main Belt Asteroids with WISE/NEOWISE I: Preliminary Albedos and Diameters
• Delivery of Dark Material to Vesta via Carbonaceous Chondritic Impacts
• A Spectroscopic Comparison of HED Meteorites and V-type Asteroids in the Inner Main Belt
• The Distribution of Basaltic Asteroids in the Main Belt
• Olivine-dominated asteroids: Mineralogy and origin
• NEOWISE Studies of Asteroids with Sloan Photometry: Preliminary Results
• Composition, Mineralogy, and Porosity of Multiple Asteroid Systems from Visible and Near-infrared Spectral Data
• A Spectroscopically Unique Main Belt Asteroid: 10537 (1991 RY16)
• More chips off of Asteroid (4) Vesta: characterization of eight Vestoids and their HED meteorite analogs
• The compositional diversity of non-Vesta basaltic asteroids
• Scattering V-type asteroids during the giant planets instability: A step for Jupiter, a leap for basalt
• Vestoids, Part II: The basaltic nature and HED meteorite analogs for eight Vp-type asteroids and their associations with (4) Vesta

Cited by in corpus (7)

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• Galactic Model Parameters and Space Density of Cataclysmic Variables in Gaia Era: New Constraints to Population Models
• Dynamical evolution of basaltic asteroids outside the Vesta family in the inner main belt
• Gaia search for early-formed andesitic asteroidal crusts
• Distribution and spectrophotometric classification of basaltic asteroids
• Spectral characterisation of 14 V-type candidate asteroids from the MOVIS catalogue
• New Insights into Erg Chech 002 Analogues in the Main Belt from Near-Infrared Spectroscopy