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Abstract Meteor radio afterglows (MRAs) and optical persistent trains (PTs) are two types of long‐lived phenomena which are occasionally observed following the occurrence of a meteor. Both phenomena are thought to be produced by intrinsic emission mechanisms; PTs have been associated with chemiluminescent reactions between meteoric metals and atmospheric ozone whereas MRA emission arises due to radiation emitted by processes in the meteor's plasma trail. Previous research has identified an association between these phenomena, and proposed a mechanism by which the reactions responsible for PTs could also fuel MRAs. In this work, we investigate said connection using a substantially larger catalog containing hundreds of examples of each phenomenon. Using meteor data from the Global Meteor Network (GMN), we performed a directed search in all‐sky radio images obtained by the Long Wavelength Array (LWA) radio telescope to identify meteors with MRAs. The resulting catalog spanned nearly 2 years and contained a total of 2,887 meteors, with 675 MRA events and 372 PTs. Statistical analyses suggest that the connection between the two phenomena is not as strong as previously supposed. Additionally, we show that the MRA occurrence rates do not have a strong seasonal dependence, meteoroid strength dependence, or preference between meteor showers and sporadics. Interestingly, we find that a meteor's entry angle appears to play a significant role in whether an MRA is observed.
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Association Between Meteor Radio Afterglows and Optical Persistent Trains
Abstract This paper presents the first observed association between meteor radio afterglows (MRAs) and persistent trains (PTs) and provides the first evidence of a link between these two phenomena. Coobservations of four meteor trails (trains) from the Long Wavelength Array (LWA) telescopes in New Mexico and the Widefield Persistent Train (WiPT) camera associate the long‐lasting (tens of seconds), self‐generated radio emission known as MRAs with the long‐lasting (tens of minutes) optical emissions known as PTs. Each of the four MRAs presented in this paper were spatially and temporally coincident with a PT. In one case, the MRA follows a relatively small (≤400 m × 400 m) noticeably bright region (knot) of emission within the PT, whereas the other three cases were associated with broader regions of PT activity. As PTs are thought to be driven by exothermic chemical reactions between atmospheric oxygen and ablation products, we show that the same reactions, specifically those involving anions, may produce the necessary suprathermal electrons to power MRAs. We show that only one part in∼1010of the available power needs to be converted to radio emission in order to produce a typical MRA.
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- Award ID(s):
- 1835400
- PAR ID:
- 10449125
- Publisher / Repository:
- DOI PREFIX: 10.1029
- Date Published:
- Journal Name:
- Journal of Geophysical Research: Space Physics
- Volume:
- 125
- Issue:
- 9
- ISSN:
- 2169-9380
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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