The history of Nuclear Pulse Propulsion can be summarized through the following events:

• August 1955: Ulam and Everett at Los Alamos propose a 12 ton ICBM propelled by nuclear blasts in LAMS-1955 On a Method of Propulsion of Projectiles by Means of External Nuclear Explosions PDF / PDF (alt).
• November 1957: Ted Taylor at at General Atomics (General Dynamics) proposes using nuclear explosions to propel a much heavier craft in GAMD-250 Note on the Possibility of Nuclear Propulsion of a Very Large Vehicle at Greater than Earth Escape Velocities.
• March 1958: Longmire, Reines and Ulam at Los Alamos propose a slightly different method of nuclear pulse propulsion in LAMS-2186 Some Schemes for Nuclear Propulsion (PDF). The same paper also proposes a Gaseous Core Rocket.
• 1958 - 1960: ARPA Project. "ORION" code-name assigned.
• 1960 - 1963: USAF Project; "Space Battleship" era.
• 1963 - 1965: NASA Project; scaled down versions launched into orbit via Saturn V.

These documents below relate to the "later" NASA period of NPP research.

GA-4891 Nuclear Pulse Vehicle Study: Condensed Summary Report (January 1964) (PDF)

GA-5009 Nuclear Pulse Space Vehicle Study: Volume I - Summary Report (Sep. 1964) (3.2~ MB PDF) (2.6~ MB Alt. PDF)

GA-5009 Nuclear Pulse Space Vehicle Study: Volume II - Vehicle Systems Performance and Costs (Sep. 1964) [Unreleased as of 2025]

GA-5009 Nuclear Pulse Space Vehicle Study: Volume III - Conceptual Vehicle Designs and Operational Systems (Sep. 1964) (7.9~ MB PDF)

GA-5009 Nuclear Pulse Space Vehicle Study: Volume IV - Mission Velocity Requirements and System Comparisons (Sep. 1964) (19.3~ MB PDF)

GA-5009 Nuclear Pulse Space Vehicle Study: Volume IV (Supplement) (Sep. 1964) (25.6~ MB PDF)

Fourth Symposium on Advanced Propulsion Concepts: Orion Space Propulsion (Technical Status and Mission Potential) (April 1965) (6.6~ MB PDF)

Nuclear Pulse Propulsion: Orion and Beyond (July 2000) (5.6~ MB PDF)