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Abstract Asteroid activity (e.g., thermo-mechanical breakdown, impacts, rotational shedding, tidal disruption) can inject meteoroids into near-Earth space and leave detectable signatures in orbit catalogs. We searched for such recent signatures using orbit-similarity statistics and explicit null-hypothesis testing applied to shower-removed, asteroidal video-meteor datasets. Our sample comprises 235,271 meteors and fireballs from four all-sky video networks (Global Meteor Network, GMN, Cameras for All-sky Meteor Surveillance, CAMS, European viDeo Meteor Observation Network Database, EDMOND, and SonotaCo). For meteors we use the geocentric dissimilarity criterion D N and construct kernel density estimator (KDE)-based sporadic null realizations to evaluate (i) global cumulative similarity distributions and (ii) localized D N -conditioned ( D N < 0.015) pair-excess maps in the ( U , λ ⊙ ) plane; we additionally apply DBSCAN ( ϵ = 0.03, <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:mi mathvariant="normal">min</mml:mi> <mml:mo>_</mml:mo> <mml:mi mathvariant="normal">samples</mml:mi> <mml:mo>=</mml:mo> <mml:mn>2</mml:mn> </mml:math> ) to isolate the coherent, statistically significant structures. We find no survey-consistent, stream-like signature in the Earth-like, low-inclination region expected for a distinct recent tidal-disruption family; instead, significant-bin membership implies, under our adopted detection thresholds and binning, a conservative combined upper limit of ≤53/235,271 ( ≤2.3 × 10 −4 ) for sporadic asteroidal meteors plausibly attributable to a detectable recent tidal-disruption-like contribution. In contrast, we confirm the detection of a new diffuse southern Virginid-region stream: GMN exhibits a local z -score of 6.32 relative to the KDE-null mean in the U − λ ⊙ phase space (global significance of 5.3 σ ), with weaker supporting excess in SonotaCo and EDMOND. DBSCAN isolates N = 282 members (243 GMN plus additional SonotaCo, CAMS, and EDMOND) on a low-perihelion, asteroidal orbit ( q = 0.22 ± 0.01 au, i = 12 <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:mover> <mml:mrow> <mml:mo>.</mml:mo> </mml:mrow> <mml:mrow> <mml:mtext>°</mml:mtext> </mml:mrow> </mml:mover> </mml:math> 3 ± 1 <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:mover> <mml:mrow> <mml:mo>.</mml:mo> </mml:mrow> <mml:mrow> <mml:mtext>°</mml:mtext> </mml:mrow> </mml:mover> </mml:math> 8, T J = 4.6 ± 0.3) consistent with near-Sun thermo-mechanical “rock-comet” activity.
Published in: The Astrophysical Journal
Volume 1000, Issue 2, pp. 254-254