Interstellar Meteors are Outliers in Material Strength

Abstract

The first interstellar meteor larger than dust was detected by US government sensors in 2014, identified as an interstellar object candidate in 2019, and confirmed by the Department of Defense in 2022. Here, we describe an additional interstellar object candidate in the CNEOS fireball catalog, and compare the implied material strength of the two objects, referred to here as IM1 and IM2, respectively. IM1 and IM2 are ranked 1 and 3 in terms of material strength out of all 273 fireballs in the CNEOS catalog. Fitting a log-normal distribution to material strengths of objects in the CNEOS catalog, IM1 and IM2 are outliers at the levels of $3.5\sigma$ and $2.6\sigma$, respectively. The random sampling and Gaussian probabilities, respectively, of picking two objects with such high material strength from the CNEOS catalog, are $\sim 10^{-4}$ and $\sim 10^{-6}$. If IM2 is confirmed, this implies that interstellar meteors come from a population with material strength characteristically higher than meteors originating from within the solar system. Additionally, we find that if the two objects are representative of a background population on random trajectories, their combined detections imply that $\sim 40\%$ of all refractory elements are locked in meter-scale interstellar objects. Such a high abundance seemingly defies a planetary system origin.

arXiv comment5 pages, 3 figures, 1 table; accepted for publication in ApJL

References in corpus (14)

• Local Kinematics and the Local Standard of Rest
• REBOUND: An open-source multi-purpose N-body code for collisional dynamics
• IAS15: A fast, adaptive, high-order integrator for gravitational dynamics, accurate to machine precision over a billion orbits
• Stars, Gas, and Dark Matter in the Solar Neighborhood
• Stellar Inventory of the Solar Neighborhood using Gaia DR1
• Depletion in post-AGB stars with a dusty disc. II
• Minimum Mass Solar Nebulae and Planetary Migration
• Bullets in a Core Collapse Supernova Remnant: The Vela Remnant
• Three Dimensional Core-Collapse Supernova Simulations with 160 Isotopic Species Evolved to Shock Breakout
• The Iron abundance in Galactic Planetary Nebulae
• Orbital characterization of superbolides observed from space: dynamical association with near-Earth objects, meteoroid streams and identification of hyperbolic meteoroids
• Hydrodynamic modelling of ejecta shrapnel in the Vela supernova remnant
• Type Ia Supernova Remnants: Shaping by Iron Bullets
• On the Possibility of an Artificial Origin for `Oumuamua

Cited by in corpus (6)

• Oort cloud perturbations as a source of hyperbolic Earth impactors
• Interstellar Meteors from Tidal Disruption of Rocky Planets on Eccentric Orbits Around M Dwarfs
• Chasing Nomadic Worlds: A New Class of Deep Space Missions
• Error dependencies in the space-based CNEOS fireball database
• The Inferred Abundance of Interstellar Objects of Technological Origin
• Close Encounters of the Interstellar Kind: Examining the Capture of Interstellar Objects in Near Earth Orbit