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The Golden (British Columbia, Canada) meteorite fall occurred on October 4, 2021 at 0534 UT with the first recovered fragment (1.3 kg) landing on an occupied bed. The associated fireball was recorded by numerous cameras permitting reconstruction of its trajectory and orbit. The fireball entered the atmosphere at a 54° angle from the horizontal at a speed of 18 km s−1. The fireball reached a peak brightness of −14, having first become luminous at a height of >84 km and ending at 18 km altitude. Analysis of the infrasonic record of the bolide produced an estimated mass of 78−65+157 kg while modeling of the fireball light curve suggests an initial mass near 70 kg. The fireball experienced a major flare near 31 km altitude where more than half its mass was lost in the form of dust and gram‐sized fragments under a dynamic pressure of 3.3 MPa. The strength and fragmentation behavior of the fireball were similar to those reported for other meteorite‐producing fireballs (Borovička et al., 2020). Seven days after the fireball occurred, an additional 0.9 kg fragment was recovered during the second day of dedicated searching guided by initial trajectory and dark flight calculations. Additional searching in the fall and spring of 2021–2022 located no additional fragments. The meteorite is an unbrecciated, low‐shock (S2) ordinary chondrite of intermediate composition, typed as an L/LL5 with a grain density of ~3530 k gm−3, an average bulk density of 3150 kg m−3 and calculated porosity of ~10%. From noble gas measurements, the cosmic ray exposure age is 25 ± 4 Ma while gas retention ages are all >2 Ga. Short‐lived radionuclides and noble gas measurements of the pre‐atmospheric size overlap with estimates from infrasound and light curve modeling producing a preferred pre‐atmospheric mass of 70–200 kg. The orbit of Golden has a high inclination (23.5°) and is consistent with delivery from the inner main belt. The highest probability (60%) of an origin is from the Hungaria group. We propose that Golden may originate among the background S‐type asteroids found interspersed in the Hungaria region. The current collection of 18 L/LL—chondrite orbits shows a strong preference for origins in the inner main belt, suggesting multiple parent bodies may be required to explain the diversity in CRE ages and shock states. [ABSTRACT FROM AUTHOR]

Background Asteroids colliding with planets vary in composition and taxonomical type. Among Near-Earth Asteroids (NEAs) are the V-types, basaltic asteroids that are classified via spectroscopic observations. Materials and Methods we performed numerical simulations and statistical analysis of close encounters and impacts between V-type NEAs and the terrestrial planets over the next 10 Myr. We study the probability of V- type NEAs colliding with Earth, Mars and Venus, as well as the Moon. We perform a correlational analysis of possible craters produced by V-type NEAs, using available catalogs for terrestrial impact craters. Results The results suggest that V-type NEAs can have many close encounters below 1 LD and even some of them impacts with all the terrestrial planets, the Earth in particular. There are four candidate craters on Earth that were likely caused by V-type NEAs. Conclusion At least 70% of the V-type NEAs can have close encounters with the terrestrial planets (and 58% with the Moon) . They can collide with all the terrestrial planets. In particular for the Earth the average rate is one every ∼12 Myr. The two craters with the highest probability of being generated by an impact with a basaltic impactor are: the Strangways crater (24 km diameter) in Australia and the Nicholson crater (12.5 km diameter) in Canada. [ABSTRACT FROM AUTHOR]

- The Grimsby meteorite (H4-6) fell on September 25, 2009. As of mid-2010, 13 fragments totaling 215 g have been recovered. Records of the accompanying fireball from the Southern Ontario Meteor Network, including six all-sky video cameras, a large format CCD, infrasound and radar records, have been used to characterize the trajectory, speed, orbit, and initial mass of the meteoroid. From the four highest quality all-sky video records, the initial entry velocity was 20.91 ± 0.19 km s−1 while the derived radiant has a local azimuth of 309.40° ± 0.19° and entry angle of 55.20° ± 0.13°. Three major fragmentation episodes are identified at 39, 33, and 30 km height, with corresponding uncertainties of approximately 2 km. Evidence for early fragmentation at heights of approximately 70 km is found in radar data; dynamic pressure of this earliest fragmentation is near 0.1 MPa while the main flare at 39 km occurred under ram pressures of 1.5 MPa. The fireball was luminous to at least 19.7 km altitude and the dynamic mass estimate of the largest remaining fragment at this height is approximately several kilograms. The initial mass is constrained to be <100 kg from infrasound data and ablation modeling, with a most probable mass of 20-50 kg. The preatmospheric orbit is typical of an Apollo asteroid with a likely immediate origin in either the 3:1 or ν6 resonances. [ABSTRACT FROM AUTHOR]