Observations of an Unexpected Meteor Shower Outburst at High Ecliptic Southern Latitude and Its Potential Origin

Abstract

A strong and unexpected meteor shower outburst was observed by the Southern Argentina Agile MEteor Radar Orbital System (SAAMER-OS) at high southern ecliptic latitude within the South Toroidal region. The outburst, which was active throughout solar longitudes 351°and 352°, peaked at 09:30 UT on 2020 March 12, has a mean Sun-centered ecliptic radiant of λ−λ 0 ∼307°.5 and β∼−77°.2 and a geocentric velocity of 30.7 km s −1 . Using the ¢ D parameter criterion, we find the corresponding orbital elements of the outburst to match well with both the β Tucanid and δ Mensid meteor showers, suggesting these are in fact the same shower. We also find a promising parent candidate in asteroid (248590) 2006 CS, a large (D∼2 km) highly inclined 52°near-Earth object.

Seasonal evolution of winds, atmospheric tides, and Reynolds stress components in the Southern Hemisphere mesosphere–lower thermosphere in 2019

“…Several of the meteor radars used in this study employ the standard meteor radar configuration of an array of five Yagi antennas for reception, with a spacing of 2 and 2.5λ (Jacobs and Ralston, 1981;Jones et al, 1998 1. Stereographic projection of the geographic location of the meteor radars used in this study and a map of the terrain elevation of Antarctica, the Antarctic Peninsula, and southern Argentina to visualize the orography around each radar station.…”

“…However, meteors at larger zenith angles are further away from the radar and, thus, are more prone to altitude errors. The typical angular precision of the employed receiver arrays is approximately 1.5-1.7 • (Jones et al, 1998). A limit of 65 • presents a more optimal choice to maximize the number of meteors entering the analysis while keeping a sufficient altitude precision.…”

Modeling the past and future activity of the Halleyid meteor showers

“…In recent years, thanks to modern numerical simulations of meteoroid streams, the timing of meteor outbursts has reached unprecedented accuracy (e.g., Asher 1999). In contrast, reliable estimates of meteor shower duration and intensity are less robust (Janches et al 2020). This is due to both a lack of measurement of the parent body's past activity and a lack of long-term, consistent records of the resulting meteor showers.…”

Meteoroids as One of the Sources for Exosphere Formation on Airless Bodies in the Inner Solar System

“…Therefore sporadic meteoroids exhibit a broad distribution of physical properties, in particular those of mass, speed, and orbital parameters. Consequently, it is very difficult to associate sporadic meteors with any particular parent body, unlike the case for many meteor showers (Jenniskens 2006;Janches et al 2020b;Hajduková and Neslusan 2020), and thus they can only be characterized through statistical measurements of the SMC's interaction with the Earth.…”

“…13, panel a) initially form azimuthally-confined arcs of trails of particles (panel b) that persist over tens of orbital revolutions of the comet until incorporated into the stream by keplerian shear (panel c). Trails are responsible for meteor outbursts: intense, but short-lived, enhancements in the visible meteor rate at Earth, over and above the activity level of the annual shower (Janches et al 2020b). In many cases, the dynamical evolution of cometary trails is deterministic (Kondrateva and Reznikov 1985;McNaught and Asher 1999;Lyytinen and Van Flandern 2000;Vaubaillon et al 2005) so meteor outbursts can be reliably forecasted with brute-force numerical simulations of test particles to serve as tracers of the dust evolution.…”