A reduced estimate of the number of kilometre-sized near-Earth asteroids
Article Abstract:
The total number of near-Earth asteroids with diameters greater than 1 km is around half the earlier estimates, according to research based on the results of the Near-Earth Asteroid Tracking programme at the Jet Propulsion Laboratory of the California Institute of Technology. The decrease of a factor of two does not significantly alter the importance of the near-Earth asteroid danger. This research has shown that continuing, automated searches offer a reliable way of characterizing the size of the near-Earth asteroid population.
Publication Name: Nature
Subject: Zoology and wildlife conservation
ISSN: 0028-0836
Year: 2000
User Contributions:
Comment about this article or add new information about this topic:
Efficient disruption of small asteroids by earth's atmosphere
Article Abstract:
Accurate modelling of the interaction between the atmosphere and an incoming bolide is a difficult task, but it is very essential to determine the fraction of small asteroids that actually hit the earth's surface. The report of the results of a large number of simulations is presented.
Publication Name: Nature
Subject: Zoology and wildlife conservation
ISSN: 0028-0836
Year: 2003
User Contributions:
Comment about this article or add new information about this topic:
Of asteroids and onions
Article Abstract:
Using thermochronometry, planetary scientists have created a theoretical model of a planetesimal's construction, revealing an internally heated object that it is made of onion-like layers with diverse cooling histories.
Publication Name: Nature
Subject: Zoology and wildlife conservation
ISSN: 0028-0836
Year: 2003
User Contributions:
Comment about this article or add new information about this topic:
- Abstracts: Effect of roost size on the emergence behaviour of pipistrelle bats. Non-nutritional maternal support in the brown long-eared bat
- Abstracts: Predator-induced nest site preference: safe nests allow courtship in sticklebacks. Increased signalling effort when survival prospects decrease: male-male competition ensures honesty
- Abstracts: Sowing nuclear misconceptions. Moral calculus and the bomb: targeting civilians, not using atomic weapons, was the moral watershed
- Abstracts: A pygostyle from a non-avian theropod. Fine structure of bone in dinosaurs, birds and mammals. Quality of the fossil record through time
- Abstracts: Evidence for evolutionary conservation of sex-determining genes. MRT-2 checkpoint protein is required for germline immortality and telomere replication in C. elegans