Asteroidal activity amongst meteor datasets: Confirmed new "rock-comet" stream and search for a tidal disruption signature

TL;DR

The paper interrogates whether asteroid-driven activity leaves detectable signatures in large meteor catalogs by searching for recent tidal-disruption fingerprints and long-term tidal distortions. It combines four all-sky video networks (GMN, CAMS, EDMOND, SonotaCo) to assemble 235{,}271 meteors after shower removal and applies KDE-based sporadic nulls, global CSDs, and localized $(U,\lambda_\odot)$ pair-excess maps, along with DBSCAN clustering, to identify coherent debris structures. A parallel analysis tests for long-term tidal signatures by comparing meteor perihelia to a debiased NEO model. The results show no robust recent tidal-disruption family, setting an upper limit of $\le 53/235271$ ($\le 2.3\times10^{-4}$) for detectable recent asteroidal contributions, while confirming a new diffuse southern Virginid-region stream (DBSCAN: $N=282$, $q=0.22\pm0.01$ au, $i=12.3^{\circ}\pm1.8^{\circ}$, $T_J=4.6\pm0.3$) with rock-comet-like activity implications. This constrains near-Sun mass-loss processes and highlights the Virginid-region stream as a target for next-generation surveys such as Rubin/LSST and NEO Surveyor.

Abstract

Asteroid activity (e.g., thermo-mechanical breakdown, impacts, rotational shedding, tidal disruption, etc.) 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 (GMN, CAMS, EDMOND, and SonotaCo). For meteors we use the geocentric dissimilarity criterion $D_N$ and construct 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 $(U,λ_\odot)$ plane; we additionally apply DBSCAN ($ε=0.03$, $\mathrm{min\_samples}=2$) 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 \emph{recent} tidal-disruption family; instead, significant-bin membership implies, under our adopted detection thresholds and binning, a conservative combined upper limit of $\leq 53/235{,}271$ ($\leq 2.3\times10^{-4}$) 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 $U-λ_\odot$ 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 ($q=0.22\pm0.01$ au, $i=12.3^{\circ}\pm1.8^{\circ}$, $T_J=4.6\pm0.3$) consistent with near-Sun thermo-mechanical ``rock-comet'' activity.

Figures (3)

• Figure 1: Cumulative similarity distribution of all possible pair combinations within the shower-removed asteroidal subsets of the GMN, CAMS, EDMOND, and SonotaCo video-meteor catalogs (N=235,271), together with the NEA sample (N=35,012), using the orbital dissimilarity metric $D_H$jopek1993remarks.
• Figure 2: Cumulative number of NEA--NEA pairs with $D_H$jopek1993remarks values below a limiting threshold. The black line uses the nominal orbital parameters, while the yellow line and shaded region include observational uncertainties. The blue-shaded area denotes the $3\sigma$ range expected from random associations based on KDE-drawn synthetic samples.
• Figure 3: Number of (a) SonotaCo--SonotaCo, (b) EDMOND--EDMOND, (c) CAMS--CAMS, and (d) GMN--GMN pairs, $N_D$, with $D_N$ values below a limiting threshold compared to the predicted number from random associations (blue line with a $3\sigma$ region) based on KDE-drawn synthetic samples simulating the sporadic background population. The black line uses the nominal observed geocentric parameters, while the yellow line and shaded region include observational uncertainties. The cumulative number of low-$D_N$ pairs is slightly in excess for three datasets, but only GMN shows an excess that remains above the uncertainty band.