Mar Tapia

The 2011 October Draconids outburst – I. Orbital elements, meteoroid fluxes and 21P/Giacobini–Zinner delivered mass to Earth

We are particularly grateful to all amateur observers that contributed to this study. We acknowledge support from the Spanish Ministry of Science and Innovation (projects AYA2009-13227, AYA2009-14000-C03-01 and AYA2011-26522), Junta de Andalucia (project P09-FQM-4555) and CSIC (grant #201050I043). We also thank the Draconid Recerca en Accio project (granted by Generalitat de Catalunya) in order to promote a cooperative amateur campaign in Catalonia. We also thank Dr Margaret Campell-Brown for many useful suggestions for improving this paper.

Analysis of a superbolide from a damocloid observed over Spain on 2012 July 13

A superbolide with an estimated absolute magnitude of -20+-1 was seen on July 13, 2012 over the center and south of Spain. This extraordinary event, which was witnessed by numerous casual observers, was recorded in the framework of the continuous fireball monitoring and meteor spectroscopy campaign performed by the SPanish Meteor Network (SPMN). Thus, because of optimal weather conditions, the bolide was imaged from ten meteor observing stations. Here we present the analysis of this magnificent event, which is the brightest fireball ever recorded by our team. The atmospheric trajectory of the bolide and the orbit in the Solar System of the parent meteoroid were obtained. The emission spectrum produced during the ablation of this particle is also discussed. We found that the meteoroid, which was following a Halley Type Comet orbit, was depleted in Na and had a tensile strength one order of magnitude higher than that corresponding to typical cometary materials. By means of orbital analysis tools we have investigated the likely parent body of this particle and the results suggest that the progenitor is a damocloid. The impact area of the hypothetical remnants of the meteoroid is also given and a search for meteorites was performed, but none were found.

Natural Hazard Associated to Shock Waves of Meter-Sized Meteoroids

The Earth’s atmosphere is a good barrier for protecting the Earth from meter-sized interplanetary projectiles but it is not fullproof. Large meteoroids or small asteroids under certain entry geometries and slow geocentric velocities, can penetrate deep into the atmosphere, and become a source of hazard to humans. The energy deposited in the atmosphere causes these bodies to ablate and the hazard can take several forms: sonic booms, airbursts, hot plasma or even crater excavation. By understanding these sources of hazards, strategies can be produced to mitigate their effects. The historic records of such unusual events are highly biased because our ancestors were probably unable to identify and classify many of them. An example is the airburst that occurred on June 30, 1908 over the Tunguska region of Siberia where several hypotheses were proposed to explain it. The recent Chelyabinsk meteorite fall, renewed our interest in the problem. This work introduces the physics and describes the main mechanisms adopted by this. It is concluded that an early detection system, capable of identifying the main sources of contemporary hazard, is needed together with planning general scenarios and safety actions.

Analisys of a superbolide from a domocloid observed over Spain on 2012 July 13

A superbolide with an estimated absolute magnitude of -20+-1 was seen on July 13, 2012 over the center and south of Spain. This extraordinary event, which was witnessed by numerous casual observers, was recorded in the framework of the continuous fireball monitoring and meteor spectroscopy campaign performed by the SPanish Meteor Network (SPMN). Thus, because of optimal weather conditions, the bolide was imaged from ten meteor observing stations. Here we present the analysis of this magnificent event, which is the brightest fireball ever recorded by our team. The atmospheric trajectory of the bolide and the orbit in the Solar System of the parent meteoroid were obtained. The emission spectrum produced during the ablation of this particle is also discussed. We found that the meteoroid, which was following a Halley Type Comet orbit, was depleted in Na and had a tensile strength one order of magnitude higher than that corresponding to typical cometary materials. By means of orbital analysis tools we have investigated the likely parent body of this particle and the results suggest that the progenitor is a damocloid. The impact area of the hypothetical remnants of the meteoroid is also given and a search for meteorites was performed, but none were found.