Asteroides y cometascuerpos progenitores de meteoritos
- Trigo Rodríguez, Josep Maria
- Madiedo Gil, Jose María
ISSN: 1132-9157
Ano de publicación: 2013
Título do exemplar: Meteoritos
Volume: 21
Número: 3
Páxinas: 293-301
Tipo: Artigo
Outras publicacións en: Enseñanza de las ciencias de la tierra: Revista de la Asociación Española para la Enseñanza de las Ciencias de la Tierra
Resumo
Asteroids and comets are the main bodies producing meteorites although the Earth also receives rocks from several planetary bodies such as the Moon, Vesta or Mars. This article deals with the diverse regions of the Solar System populated by these so-called minor bodies in order to explain the dynamic mechanisms allowing the transport of meteorites to the Earth. We also introduce the reader to the main criteria that allow us to perform isotopic dating of the transport times from the time in which the meteorites were in their asteroids or comets: Cosmic Ray Exposure Ages (CREAs). These ages show that our Solar System is a highly dynamic system, apparently stable at our human time-scale, but subject to large collisions that take place in the main asteroid belt. Nowadays, most meteorites that reach the Earth were released tens of millions of years ago from their parent asteroids due to colossal impacts. Just these tens of meters in diameter asteroidal fragments are nowadays one of the most significant sources of impact hazard for Earth