First Results from the Rapid-Response Spectrophotometric Characterization of Near-Earth Objects using UKIRT

TL;DR

This study rapidly characterizes near-Earth objects using infrared photometry from UKIRT, enabling classification of small, recently discovered NEOs and providing insights into their composition and population distribution.

Contribution

It introduces a rapid-response observational method combined with machine learning for near-infrared classification of small, newly discovered NEOs.

Findings

Distinguished between different asteroid taxonomic types.

Found a lower fraction of S-complex asteroids compared to meteorite data.

Demonstrated the effectiveness of rapid infrared observations for NEO characterization.

Abstract

Using the Wide Field Camera for the United Kingdom Infrared Telescope, we measure the near-infrared colors of near-Earth objects (NEOs) in order to put constraints on their taxonomic classifications. The rapid-response character of our observations allows us to observe NEOs when they are close to the Earth and bright. Here we present near-infrared color measurements of 86 NEOs, most of which were observed within a few days of their discovery, allowing us to characterize NEOs with diameters of only a few meters. Using machine-learning methods, we compare our measurements to existing asteroid spectral data and provide probabilistic taxonomic classifications for our targets. Our observations allow us to distinguish between S-complex, C/X-complex, D-type, and V-type asteroids. Our results suggest that the fraction of S-complex asteroids in the whole NEO population is lower than the fraction of ordinary chondrites in the meteorite fall statistics. Future data obtained with UKIRT will be used to investigate the significance of this discrepancy.