Characterization of the June epsilon Ophiuchids meteoroid stream and the comet 300P/Catalina

Abstract

Aims. Prior to 2019, the June epsilon Ophiuchids (JEO) were known as a minor unconfirmed meteor shower with activity that was considered typically moderate for bright fireballs. An unexpected bout of enhanced activity was observed in June 2019, which even raised the possibility that it was linked to the impact of the small asteroid 2019 MO near Puerto Rico. Early reports also point out the similarity of the shower to the orbit of the comet 300P/Catalina. We aim to analyze the orbits, emission spectra, and material strengths of JEO meteoroids to provide a characterization of this stream, identify its parent object, and evaluate its link to the impacting asteroid 2019 MO. Methods. Our analysis is based on a sample of 22 JEO meteor orbits and four emission spectra observed by the AMOS network at the Canary Islands and in Chile. The meteoroid composition was studied by spectral classification based on relative intensity ratios of Na, Mg, and Fe. Heliocentric orbits, trajectory parameters, and material strengths were determined for each meteor and the mean orbit and radiant of the stream were calculated. The link to potential parent objects was evaluated using a combination of orbital-similarity D-criteria and backwards integration of the orbit of comet 300P and the JEO stream. Results. We confirm the reports of an unexpected swarm of meteoroids originating in the JEO stream. JEO meteoroids have low material strengths characteristic for fragile cometary bodies, and they exhibit signs of a porous structure. The emission spectra reveal slightly increased iron content compared to all other measured cometary streams, but they are generally consistent with a primitive chondritic composition. Further dynamical analysis suggests that the JEO stream is likely to originate from comet 300P/Catalina and that it was formed within the last 1000 years. Over longer timescales, the meteoroids in the stream move to chaotic orbits due to the turbulent orbital evolution of the comet. Our results also suggest that the impact of the small asteroid 2019 MO on June 22 was not connected to the JEO activity.

Hydrogen emission from meteors and meteorites: mapping traces of H$_{2}$O molecules and organic compounds in small Solar system bodies

“…The meteor and meteor spectra observations used in this work were captured by the global All-sky Meteor Orbit System (AMOS) network. The AMOS network, operated by the Comenius University in Bratislava, currently consists of 14 standard AMOS systems providing trajectory and orbital data (Tóth et al 2015(Tóth et al , 2019 and 8 spectral systems AMOS-Spec providing spectral data (Rudawska et al 2016;Matlovič et al 2019Matlovič et al , 2020b. AMOS systems are located at five stations in Slovakia, two stations in the Canary Islands, two stations in Chile, two stations in Hawaii and three stations in Australia.…”

High frame rate emission spectroscopy for ablation tests in plasma wind tunnel

“…In the High Enthalpy Flow Diagnostics Group (HEFDiG) of the Institute of Space Systems at the University of Stuttgart, meteoroid entry scenarios are investigated in order to provide datasets needed by observers and meteor physicists and to support the fundamental study of meteoroids. The recording of meteor spectra helps in understanding the elemental composition of meteoroids 7 and possible estimation of their trajectory and orbital parameters 8 and ultimately identifying their parent bodies such as asteroids and comets. Meteor spectra have been recorded by direct observation during meteor showers and by constant monitoring of the night sky, for example, using the global All-sky Meteor Orbit System (AMOS) meteor network 9 and at a few other locations across the world.…”