The Hamburg Meteorite Fall: Fireball trajectory, orbit and dynamics

Abstract

The Hamburg (H4) meteorite fell on January 17, 2018 at 01:08 UT approximately 10km North of Ann Arbor, Michigan. More than two dozen fragments totaling under one kilogram were recovered, primarily from frozen lake surfaces. The fireball initial velocity was 15.83 $\pm$ 0.05 km/s, based on four independent records showing the fireball above 50 km altitude. The radiant had a zenith angle of 66.1 $\pm$ 0.29 degs and an azimuth of 121.56 $\pm$ 1.2 degs. The resulting low inclination ($<$ 1 deg) Apollo-type orbit has a large aphelion distance and Tisserand value relative to Jupiter (Tj) of $\sim$ 3. Two major flares dominant the energy deposition profile, centred at 24.1 and 21.7 km altitude respectively under dynamic pressures of 5-7 MPa. Our preferred total energy for the Hamburg fireball is 2 to 7 T TNT (8.4 to 28 x 10${}^9$ J), which corresponds to a likely initial mass in the range of 60 to 225 kg or diameter between 0.3 to 0.5 m. Based on the model of Granvik et al (2018), the meteorite originated in an escape route from the mid-outer asteroid belt. Hamburg is the 14th known H-chondrite with an instrumentally-derived pre-atmospheric orbit, half of which have small ($<$5 deg) inclinations making connection with (6) Hebe problematic. A definitive parent body consistent with all 14 known H-chondrite orbits remains elusive

arXiv comment85 pages, 4 tables, 15 figures, 1 appendix. Accepted to Meteoritics and Planetary Science, June 19, 2019

References in corpus (9)

• Debiased orbit and absolute-magnitude distributions for near-Earth objects
• Multiple and Fast: The Accretion of Ordinary Chondrite Parent Bodies
• Identification of meteorite source regions in the Solar System
• Modeling the measurement accuracy of pre-atmosphere velocities of meteoroids
• Optical Observations of Meteors Generating Infrasound - I: Acoustic Signal Identification and Phenomenology
• 3D shape of asteroid (6)~Hebe from VLT/SPHERE imaging: Implications for the origin of ordinary H chondrites
• Small Near-Earth Asteroids as a Source of Meteorites
• Estimating trajectories of meteors: an observational Monte Carlo approach -- II. Results
• The frequency of window damage caused by bolide airbursts: a quarter century case study

Cited by in corpus (6)

• A Global Fireball Observatory
• Data on 824 fireballs observed by the digital cameras of the European Fireball Network in 2017-2018. II. Analysis of orbital and physical properties of centimeter-sized meteoroids
• Direct measurement of decimeter-sized rocky material in the Oort cloud
• Oxygen line in fireball spectra and its application to satellite observations
• A Two Year Survey for VLF Emission from Fireballs
• Statistical significance of meteorite-asteroid pairs using geocentric parameters