Historical records of δ-Arietids superfireballs over Spain

Abstract

Historical reports of bright fireballs are useful to better understand which meteoroid streams can be temptatively associated with meteoritedropping events [1]. We present here a preliminary analysis of a very remarkable event that took place over Spain on Dec. 8, 1932 and the evidences that support its likely connection to the δ-Arietids meteor shower. Besides, there is evidence that indicate that another very bright, although less important, event was witnessed over the same region during the same day could be also associated to this shower. The δ-Arietids is a minor shower which is included in the IAU working list of meteor showers with the code 289 DNA [2]. Very few data exist for this radiant and, so, any new contributions about it are of great interest. The densities calculated for δ-Arietids meteoroids are comprised between 2000 and 5000 kg/m3, which suggest that that their parent body must be an asteroid [3]. Thus, one NEO, asteroid 1990 HA (217628 Lugh), has been proposed as the parent body for this shower [4]. This is an Apollo family asteroid with a diameter of about 1.4 km which is catalogued as a PHA. Moreover, this shower has been proposed as a candidate for potential meteorite dropping events, and one fireball recorded on Dec. 13, 1975 is believed to have produced a meteorite with a surviving terminal mass of about 290 g. [3, 4]. 1990 HA is not, however, the only NEO which has been reported to be able to produce meteorites. Thus, recently, asteroid 2002NY40 was proven to be the source of meteorite dropping bolides [5].