A 2012 geminid fireball : atmospheric trajectory, orbit and spectrum

Abstract

Asteroid (3200) Phaeton is the par- ent body of the Geminid meteoroid stream. These par- ticles give rise to one of the strongest annual meteor showers, with an activity period that extends from Nov. 27 to Dec. 28, peaking on Dec. 14 [1]. Ceplecha and McCrosky concluded that the bulk density of Geminid meteoroids is of about 3–4 g/cm 3 [2]. How- ever, Babadzhanov obtained a value of 2.9 g/cm 3 [3]. It is possible that the high density of Geminid meteor- oids in comparison with other meteoroids is due to the small perihelion distance of the Geminid orbit (q=0.141). This, in fact, would cause a depletion in the most volatile elements. One common technique to ana- lyze the composition of Geminid meteoroids is meteor spectroscopy. Thus, the SPanish Meteor Network em- ploys an array of CCD video spectrographs to deter- mine the chemical nature of meteoroids ablating in the atmosphere. In this work we present the analysis of a bright Geminid bolide (absolute magnitude -10) ob- served over the south and center of Spain in 2012. Its spectrum was recorded from three of our meteor ob- serving stations.