Mineralogy of V-type asteroids as a constraining tool of their past history

Abstract

a b s t r a c tIn the past few years, the genetic relationship between (4) Vesta, Vestoids and HED meteorites was reinforced (Drake, 2001, Meteorit. Planet. Sci. 36 (4), 501-513). It is believed that Vestoids and HED meteorites were originated from a collision suffered by (4) Vesta, during the early stages of the Solar System. Due to the effects of dynamical resonances, several fragments of this collision were ejected into near-Earth orbits and some of them have originated the so-called HED meteorites. We aim to infer about the hypothetical collision suffered by (4) Vesta and its connection to the genetic relationship between V-type asteroids and HED meteorites. For this purpose, reflectance spectra of a set of 11 V-type asteroids and 55 HED meteorites were obtained, respectively, from the publically available MIT-UH-IRTF Joint Campaign for NEO Reconaissance and RELAB database.Initially, for each of the selected V-type asteroids, we attempted to identify its meteoritic analogue. Afterwards, we have performed a numerical spectral analysis based on the Hapke radiative transfer model. We report the inferred surface composition and mineralogy of the V-type asteroids, for which we have identified a meteoritic analogue.Our results strength the relationship between HED meteorites and V-type asteroids, as also suggested by the results from the Dawn mission (de Sanctis et al., 2012, Science, 336 (6082), 697-690;2013 Meteorit. Planet. Sci. 48 (11) 2166-2184 McSween et al., 2011, Space Sci. Rev. 163 (1-4), 141-174;2013, Meteorit. Planet. Sci. 48 (11) 2090-2104. The latter is contradicting the results from Schiller et al. (2011, Astrophys. J. 740 L22) and Wasson (2013, Earth Planet. Sci. Lett. 381 138-146), which questioned this linkage. We also report the best meteoritic kind for the studied V-type asteroids, by comparing their spectra and mineralogies. We also report the pyroxenes mineralogical distributions of the HED meteorites, inferred through the Hapke radiative transfer model, which can be suitable for comparison with future mineralogical studies of these objects.

Can Formulas Derived From Pyroxenes and/or HEDs Be Used to Determine the Mineralogies of V‐Type Asteroids?

“…Batista et al () found that the best spectral matches for Nyx, Magellan, 1992 FE, and 1993 WW were howardites. Ieva et al () argued that Midas, Nyx, Magellan, 1993 VW, and 1994 LX had surface mineralogies similar to eucrites.…”

“…However, if the same specific meteoritic interpretation was verified using a second technique (e.g., absorption band modeling and radiative transfer modeling), more specific interpretations would be much more easily justified. For example, Batista et al () found that the best spectral matches for Nyx, Magellan, 1992 FE, and 1993 WW were howardites. Ieva et al () used a number of spectral parameters that they derived from both HEDs and V‐types and argued that Midas, Nyx, Magellan, 1993 VW, and 1994 LX had surface mineralogies similar to eucrites.…”

“…The uncertainty for the given Fs content, which is derived from the Band I center, is ±4 mol%, and the uncertainty for the given Wo content, which is derived from the Band I center, is ±1 mol%. Batista et al (2014) found that the best spectral matches for Nyx, Magellan, 1992 FE, and 1993 WW were howardites. Ieva et al (2016) argued that Midas, Nyx, Magellan, 1993 VW, and 1994 LX had surface mineralogies similar to eucrites.…”