  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
