Multi-station fireball observations combining all-sky spectroscopy and optical trajectory measurements
-
Abstract
Optical monitoring of fireballs can provide reconstructions of luminous trajectories and derivation of heliocentric orbits, while spectral observations are able to supply information from an entirely different perspective, with composition and material data. Observing and analyzing a fireball using both methods enables the complete characterization of its meteorite properties. We simultaneously collected luminous and spectral observations of fireballs through observation networks established in eastern China and the Western Cape of South Africa. The optical observations employed 180°×180° fisheye cameras, while spectral data were recorded by fixing gratings in front of each camera lens on the Allsky7 instrument, so that both could monitor fireballs within an all-sky field of view. The spectra have an effective resolution of R = 200.
During the first year of operation, the network detected spectra from 150 fireballs, most of which recognized at least Mg I and Na I emission lines, some of them were recorded both spectral and trajectory. Preliminary analysis of four bright fireballs indicates they can be categorized as asteroidal orbits or Halley-type cometary orbits, with spectra classified as normal, Fe-rich, Iron, and Na-poor respectively.
One Halley-type fireball belongs to the Perseid meteor shower. For the two fireballs on asteroid-like orbits, orbital comparisons with known NEAs were performed using multiple D-criteria. Under the D_N criterion, SAFB20250713 (Iron type) shows a loose possible match with 2021 BD, whereas JsFB20250110 (Fe-rich type) exhibits a closer potential similarity with 2017 BK (D_N = 0.03). Overall, the orbital comparison indicates possible associations but no definitive parent bodies, while the spectral characteristics are broadly consistent with the asteroid-like or comet-like nature implied by their orbital classes.
-
-