Orbital Characterization of Superbolides Observed from Space: Dynamical Association with Near-Earth Objects, Meteoroid Streams, and Identification of Hyperbolic Meteoroids

Abstract

There is an unceasing incoming flux of extraterrestrial materials reaching the Earth atmosphere. Some of these objects produce luminous columns when they ablate during the hypersonic encounter with air molecules. A few fireballs occur each year bright enough to be detected from space. The source of these events is still a matter of debate, but it is generally accepted that they are of sporadic origin. We studied the NASA-JPL Center for NEOs Studies (CNEOS) fireball database to infer the dynamic origin of large bolides produced by meter-sized projectiles that impacted our planet. These likely meteorite-dropping events were recorded by the US Government satellite sensors. We estimated the false-positive rate and analyzed the time evolution of multiple orbit dissimilarity criteria concerning potential associations with near-Earth objects and meteoroid streams. We found that at least 16% of the large bolides could be associated with meteoroid streams, about 4% are likely associated with near-Earth asteroids, and 4% may be linked to near-Earth comets. This implies that a significant fraction of meter-sized impactors producing large bolides may have an asteroidal or cometary origin. In addition, we found at least three bolides having hyperbolic orbits with high tensile strength values. Meter-sized meteoroids of interstellar origin could be more common than previously thought, representing about 1% of the flux of large bolides. The inferred bulk physical properties suggest that the interstellar medium could bias these projectiles toward high strength rocks with the ability to survive prolonged exposure to the harsh interstellar space conditions.

Multi-instrument observations of the Pajala fireball: Origin, characteristics, and atmospheric implications

“…Such a propagation should be limited by chaos indicators and may hence not yield an association (e.g., Cincotta and Simó, 2000). Additionally, during this backwards propagation, there are several metrics that can be used to indicate dynamical association (Trigo-Rodriguez et al, 2007;Peña-Asensio et al, 2022). However, such an in depth dynamical investigation is outside the scope of the current study.…”

Identifying meteorite droppers among the population of bright 'sporadic' bolides imaged by the Spanish Meteor Network during the spring of 2022

“…Recent studies also show large percentages of meteors associated with meteor showers, for example, 45% in Colas et al (2020) and35% in Drolshagen et al (2021). Regarding superbolides detected from space, 23% could be associated with meteoroid streams or near-Earth objects (Peña-Asensio et al 2022).…”

“…From the observation and analysis of fireballs with ground-based multi-stations, more than 10 major showers have been established (Quadrantids, April Lyrids, 𝜂-Aquarids, Southern 𝛿-Aquariids, Perseids, Orionids, Taurids, Leonids, Geminids and Ursids), that is, meteoroid streams that present activity of more than 10-15 meteors per hour (Bagnall 2021). However, there are hundreds of minor showers with lower activities as well as near-Earth asteroids, many of them poorly studied, that can produce bright fireballs and, therefore, potentially meteorite dropper events, just as being a source of impact hazard to the Earth (Voloshchuk & Kashcheev 1996;Halliday 1987;Madiedo & Trigo-Rodríguez 2008;Borovička et al 2015;Trigo-Rodríguez et al 2017;Trigo-Rodríguez & Blum 2022;Peña-Asensio et al 2022).…”

Interstellar Meteors Are Outliers in Material Strength

“…The probability of randomly drawing two of the top three material strengths out of all 273 fireballs is ∼(3/273) 2 ∼ 10 −4 . Therefore, if IM2 is confirmed to be an interstellar meteor, simple random drawing dictates that there would be a ∼99.99% chance that interstellar meteors come from a population with material strength characteristically higher than meteors originating from within the solar system, a notion suggested by Peña-Asensio et al (2022).…”

“…In this Letter, we describe an interstellar meteor candidate from the CNEOS catalog mentioned in Table 8 of Peña-Asensio et al (2022) and in Section 5 of Siraj & Loeb (2022b), which we refer to as IM2. We then explore the statistical likelihood that interstellar meteors reflect the same distribution of material strength as noninterstellar meteors.…”