Meteor Radio Afterglows: HF and VHF Radio Emission from Meteor Trails

The serendipitous discovery of broadband HF/VHF radio emission from meteor trails has opened a new door into observing meteors and raises new questions about meteor plasma physics. These transient events, referred to as meteor radio afterglows (MRAs), last for 10s to 100s of seconds after the ablation of a meteor, and only occur for meteors or portions thereof above ∼ 90 km. Light curves typically follow a fast rise and slow decay, and the spectra have been shown to follow a steep frequency dependent power law, getting brighter at lower frequencies. This discovery and further followup studies were made possible by advancements in many element HF/VHF radio telescopes, specifically the all-sky imaging capabilities of the LWA telescopes. In this paper we summarize the past and ongoing research on this new topic.