The Global Meteor Network -- Methodology and First Results

• Main Authors: Vida, Denis, Šegon, Damir, Gural, Peter S, Brown, Peter G, McIntyre, Mark J. M, Dijkema, Tammo Jan, Pavletić, Lovro, Kukić, Patrik, Mazur, Michael J, Eschman, Peter, Roggemans, Paul, Merlak, Aleksandar, Zubović, Dario
• Format: Journal Article
• Language: English
• Published: 29-07-2021
• Subjects: Physics - Earth and Planetary Astrophysics; Physics - Instrumentation and Methods for Astrophysics
• DOI: 10.48550/arxiv.2107.12335

The Global Meteor Network (GMN) utilizes highly sensitive low-cost CMOS video
cameras which run open-source meteor detection software on Raspberry Pi
computers. Currently, over 450 GMN cameras in 30 countries are deployed. The
main goal of the network is to provide long-term characterization of the
radiants, flux, and size distribution of annual meteor showers and outbursts in
the optical meteor mass range. The rapid 24-hour publication cycle the orbital
data will enhance the public situational awareness of the near-Earth meteoroid
environment. The GMN also aims to increase the number of instrumentally
observed meteorite falls and the transparency of data reduction methods. A
novel astrometry calibration method is presented which allows decoupling of the
camera pointing from the distortion, and is used for frequent pointing
calibrations through the night. Using wide-field cameras
($88^{\circ}\times48^{\circ}$) with a limiting stellar magnitude of $+6.0 \pm
0.5$ at 25 frames per second, over 220,000 precise meteoroid orbits were
collected since December 2018 until June 2021. The median radiant precision of
all computed trajectories is $0.47^{\circ}$, $0.32^{\circ}$ for $\sim20\%$ of
meteors which were observed from 4+ stations, a precision sufficient to measure
physical dispersions of meteor showers. All non-daytime annual established
meteor showers were observed during that time, including five outbursts. An
analysis of a meteorite-dropping fireball is presented which showed visible
wake, fragmentation details, and several discernible fragments. It had spatial
trajectory fit errors of only ~40 m, which translated into the estimated
radiant and velocity errors of 3 arc minutes and tens of meters per second.