G. Cevolani et al., THE [[LUGO]] FIREBALL OF JANUARY 19, 1993, Nuovo cimento della Societa italiana di fisica. C, Geophysics and space physics, 16(4), 1993, pp. 463-471
Observational data and the theory of the interaction of meteoroids wit
h the Earth's atmosphere enable us to characterize the spectacular fir
eball which was observed to cross Northern Italy from SE to NW on Janu
ary 19, 1993, ending at about 00:33 h UT with an explosion approximate
ly over the town of Lugo di Romagna. For estimated visual magnitudes M
(v)=-22 divided by-25 at the peak of the light curve corresponding to
values of an initial radius of (1.5 divided by 3) m, a meteor luminosi
ty ranging between 3 . 10(18) and 4 . 10(19) erg/s is obtained, consis
tent with the radiant flux values obtained by the Stefan-Boltzmann law
for a black-body temperature of tens of thousand degrees. The explosi
on of the bolide produced low-frequency ((1.5 divided by 2) Hz) infras
onic waves which were monitored by a microseismic network of three sta
tions near Ferrara and by regional seismic stations of the ING (Istitu
to Nazionale di Geofisica) at (20 divided by 60) km distances from the
epicentre located in the stratosphere. The analysis of recovered micr
oremnants nearby the epicentre in the form of spherules of vaporized a
nd recondensed material, outlines the relative importance of light che
mical elements typical of soft structures in small Earth-crossing bodi
es.