Asteroids and Comets

5 July 2005

Asteroids and Comets

Asteroids and comets are thought to be remnant material from the processes of formation and initial development of planets. Due to their peculiar dynamical and physical properties, such as small size, lack of a permanent atmosphere, and relatively little thermal processing, these objects constitute a special class of planetary body.

In many cases the material from which asteroids and comets are made may have remained largely unaltered since the time of solar system formation, thus these objects should contain a wealth of information on conditions in the protoplanetary nebula. Scientific interest in asteroids and comets stems mainly from the crucial role they appear to have played in the formation of the planets and the development of life. However, in recent years the recognition of the hazard posed to civilization from impacts on the Earth of asteroids and comets, in particular near-Earth objects (NEOs), has led to increased efforts to understand the nature of these objects, and to investigations into the exact magnitude of the impact risk and how a future potentially catastrophic collision may be avoided.

Research topics

  • The physical and dynamical properties of asteroids and comets.
  • Modeling of orbital evolution over long time scales.
  • The origin of the material in asteroids and comets and how internal and external processes modify it.
  • The properties of cometary nuclei, the origin of cometary activity, the chemical processes in the coma, and the interaction of cometary ions with the solar wind.
  • Simulations of the impacts of asteroids and comets on planetary surfaces using hydrodynamic codes.
  • The impact probability of NEOs on the Earth and investigations of suitable mitigation techniques.
  • The role played by asteroids and comets in the development of planets and life on Earth.

Our activities also include contributions to relevant space projects of ESA, NASA and other space agencies, such as mission planning, the development of scientific instruments and the reduction and analysis of resulting data. We also carry out astronomical observations of asteroids and comets with major telescopes on the ground and in space and develop computer models to aid in the interpretation of the data.

Dr.rer.nat. Ekkehard K├╝hrt
German Aerospace Center

Institute of Planetary Research
, Asteroids and Comets
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