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
The content above is only an excerpt.
for your institution. Subscribe
To learn more about subscribing to AccessScience, or to request a no-risk trial of this award-winning scientific reference for your institution, fill in your information and a member of our Sales Team will contact you as soon as possible.
to your librarian. Recommend
Let your librarian know about the award-winning gateway to the most trustworthy and accurate scientific information.
AccessScience provides the most accurate and trustworthy scientific information available.
Recognized as an award-winning gateway to scientific knowledge, AccessScience is an amazing online resource that contains high-quality reference material written specifically for students. Its dedicated editorial team is led by Sagan Award winner John Rennie. Contributors include more than 9000 highly qualified scientists and 42 Nobel Prize winners.
MORE THAN 8500 articles and Research Reviews covering all major scientific disciplines and encompassing the McGraw-Hill Encyclopedia of Science & Technology and McGraw-Hill Yearbook of Science & Technology
115,000-PLUS definitions from the McGraw-Hill Dictionary of Scientific and Technical Terms
3000 biographies of notable scientific figures
MORE THAN 17,000 downloadable images and animations illustrating key topics
ENGAGING VIDEOS highlighting the life and work of award-winning scientists
SUGGESTIONS FOR FURTHER STUDY and additional readings to guide students to deeper understanding and research
LINKS TO CITABLE LITERATURE help students expand their knowledge using primary sources of information