Engineering:Ivan's hammer

Ivan's Hammer refers to the hypothetical use of a natural asteroid or meteoroid as a weapon of mass destruction in a first-strike role. The concept can be traced back to the 1960s. At the annual meeting of the American Astronautical Society, in January, 1962 Dandridge M. Cole warned that as early as 1970 the Soviets could develop the technology to divert a near earth asteroid to impact a target on earth. During the late 1960s and early 1970s a number of science fiction writers used the concept in story ideas, most notably Robert Heinlein in The Moon is a Harsh Mistress (1966) where a rebellious Lunar colony uses large payloads of mined ore to bombard Earth from the Moon; Rendezvous with Rama by Arthur C. Clarke (1972); and Lucifer's Hammer by Larry Niven and Jerry Pournelle (1977). Modified concepts that utilized large man-made constructions can be seen in Mobile Suit Gundam and its derivative series, where large space colonies were dropped onto Earth, sometimes right onto population centers.

A RAND Corporation study from 2002 also discusses the method and feasibility of such an application. The American astronomer Carl Sagan warned about the possibility of asteroid deflection technology being used as a weapon in several works, describing a "deflection dilemma" for projects seeking to address the asteroid impact hazard.

See also

• Directed-energy weapon
• Laser weapon
• Space weapon
• Kinetic bombardment