Do L chondrites come from the Gefion family?

TL;DR

This study investigates whether the Gefion asteroid family is the source of L chondrites by analyzing near-infrared spectra of family members, finding no evidence of L chondrite composition among them.

Contribution

The paper provides observational spectral data to test the hypothesized link between the Gefion asteroid family and L chondrites, challenging previous dynamical models.

Findings

Gefion family members show diverse compositions, including H chondrites and achondrites.

No spectral evidence of L chondrites was found among the sampled asteroids.

The diversity suggests the parent body may be partially differentiated or contains interlopers.

Abstract

Ordinary chondrites (H, L, and LL chondrites) are the most common type of meteorites comprising 80 per cent of the meteorites that fall on Earth. The source region of these meteorites in the main asteroid belt has been a basis of considerable debate in the small bodies community. L chondrites have been proposed to come from the Gefion asteroid family, based on dynamical models. We present results from our observational campaign to verify a link between the Gefion asteroid family and L chondrite meteorites. Near-infrared spectra of Gefion family asteroids (1839) Ragazza, (2373) Immo, (2386) Nikonov, (2521) Heidi, and (3860) Plovdiv were obtained at the NASA Infrared Telescope Facility (IRTF). Spectral band parameters including band centres and the band area ratio were measured from each spectrum and used to constrain the composition of these asteroids. Based on our results, we found that some members of the Gefion family have surface composition similar to that of H chondrites, primitive achondrites, and basaltic achondrites. No evidence was found for L chondrites among the Gefion family members in our small sample study. The diversity of compositional types observed in the Gefion asteroid family suggests that the original parent body might be partially differentiated or that the three asteroids with non-ordinary chondrite compositions might be interlopers.