High-resolution radar observations of meteoroid fragmentation and flaring at the Jicamarca Radio Observatory

作者：Zhu Qian^*; Dinsmore Ross; Gao Boyi; Mathews John D^*

来源：Monthly Notices of the Royal Astronomical Society, 2016, 457(2): 1759-1769.

DOI：10.1093/mnras/stw070

• techniques: radar astronomy
• meteorites
• meteors
• meteoroids

Although meteoroid fragmentation has been observed and studied in the optical meteor community since the 1950s, no definitive fragmentation mechanisms for the relatively small meteoroids (mass a parts per thousand(2)10(-4) kg) have been proposed. This is in part due to the lack of observations to constrain physical models of the fragmentation process. While it is challenging to record fragmentation in faint optical meteors, observing faint meteors using High-Power, Large-Aperture coherent radars can yield considerable micrometeoroid fragmentation information especially when employing interferometric imaging. Radar interferometric imaging can potentially resolve the fragmentation process in three spatial dimensions by monitoring the evolution of the plasma in the meteor head-echo, flare-echo, and trail-echo regions. We present results of applying a newly developed hybrid interferometric-CS (compressed sensing) technique (H-ICS) to radar meteor observations conducted at the Jicamarca Radio Observatory in Peru. With the H-ICS technique - which provides improved spatial resolution over earlier techniques - we analyse five representative meteoroid fragmentation events. Results include observations of both along and transverse to the trajectory spreading of the developing plasma apparently caused by gross fragmentation and plasma diffusion parallel to the geomagnetic field near the geomagnetic equator.

• 出版日期2016-4-1