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The Interstellar Society
Newsletters, discussions and design concepts for interstellar exploration of space offered by a non-profit organization.
http://www.interstellarsociety.org/
The Preparation
Links between nanotechnology and space colonization; essays on the transhuman future.
http://thepreparation.com/
The Preparation: Space Colonization
Detailed discussion by Rex Stephens about his book on the need for space colonization, asteroid mining, and transhumans.
http://thepreparation.net
The Space Frontier Foundation
Articles, discussion sites, meetings, and government advocacy dedicated to opening the space frontier as rapidly as possible.
http://www.space-frontier.org
The Space Settlement Institute
A non-profit association founded to help promote space colonization; emphasis on property rights law.
http://www.space-settlement-institute.org
