CAMO-S: A meteor-tracking spectrograph at the Canadian Automated Meteor Observatory

TL;DR

The paper introduces CAMO-S, a spectral meteor-tracking spectrograph at the Canadian Automated Meteor Observatory, capable of detailed spectral analysis of meteors and fragments, enhancing understanding of meteoroid composition and fragmentation behavior.

Contribution

It presents the design, calibration, and initial results of a new spectral system integrated with CAMO for detailed meteor spectroscopy and fragment analysis.

Findings

Spectral resolution of about 1 nm/pixel achieved.

Identification of Ca II H and K lines in meteor spectra.

Observation of unusual fragmentation behavior in Fe-rich meteors.

Abstract

The Canadian Automated Meteor Observatory (CAMO) mirror tracking system has been in operation since 2009 and has, to date, produced more than 20,000 two-station meteor observations at meter-level spatial and 10 ms temporal resolution. In 2020, a spectral tracking camera was added in parallel at one of the CAMO stations. To date, it has recorded the spectra of hundreds of faint meteors. Engineering testing from 2020-2023 resulted in the selection of a 150 lpmm grating and an EMCCD camera to achieve a spectral resolution of about 1 nm/pixel in the final configuration. The CAMO spectral system can resolve spectra from individual meteoroid fragments, record spectra for meteors of +2 peak magnitude to as faint as +4 in parts of the lightcurve and produce relative abundance estimates for Mg, Fe and Na. Our preliminary results also show identification of the H and K lines of CA(II). Meteors with strong iron lines were found to have unusual fragmentation behaviour, involving gross fragmentation rather than continuously shedding small particles. The spectra of individual fragments can be resolved in some cases, showing that these Fe-rich objects do not differ in composition among fragments. Our calibration procedure and hardware configuration are discussed together with preliminary results.