Defense against killer asteroids
Syal, Megan Bruck Lawrence Livermore National Laboratory, Livermore, California.
- Nature of the threat
- Planetary defense options
- Current planetary defense research
- Links to Primary Literature
- Additional Readings
Today scientists recognize that impact craters on the Earth, the Moon, and other solar system bodies were created by very high speed collisions with asteroids and comets. However, the Earth's violent history of bombardment has been acknowledged only relatively recently. Meteor Crater in northern Arizona was the first terrestrial crater confirmed to have formed from an asteroid impact, following fieldwork investigations by Gene Shoemaker in the 1950s. Shortly thereafter, estimates of the impact rate in the Earth-Moon system improved rapidly after successful lunar sample return, which allowed precise age-dating of particular cratered regions of the Moon. Since the 1990s, the rise of dedicated telescopic surveys to detect and characterize the orbits of near-Earth objects has further refined estimates of the current asteroid population. See also: Asteroid; Comet; Meteorite; Moon; Sloan Digital Sky Survey; WISE spacecraft
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