1. Michael Krepon and Samuel Black, "Space Security or Antisatellite Weapons?" Henry L. Stimson Center, May 2009. Available at http://www.stimson.org/pub.cfm?ID=828 .
2. "Precision-guided munitions" is a term that encompasses GPS-guided weapons as well as laser-guided bombs and weapons using other guidance concepts. However, the Joint Direct Attack Munition and Joint Stand-Off Weapon, two widely used munitions within the precision-guided category, are both guided by the U.S. GPS satellite navigation system. Carl Conetta, "Catastrophic Interdiction: Air Power and the Collapse of the Iraqi Field Army in the 2003 War," Commonwealth Institute Project on Defense Alternatives, Briefing Memo #30, September 26, 2003. Available at http://www.comw.org/pda/fulltext/0309bm30.pdf .
3. David Wright, Laura Grego, and Lisbeth Gronlund, The Physics of Space Security (Cambridge, MA: American Academy of Arts & Sciences, 2005).
4. Kelly Young, "Anti-satellite Test Generates Dangerous Space Debris," New Scientist , January 20, 2007. Available at http://www.newscientist.com/article/dn10999 ; "US Missile Hits 'Toxic Satellite,'" BBC News , February 21, 2008. Available at http://news.bbc.co.uk/2/hi/science/nature/7254540.stm .
5. David Wright, "Space Debris," Physics Today , October 2007, pp. 35-40; Union of Concerned Scientists, "Space Debris from Anti-Satellite Weapons," April 2008. Available at http://www.ucsusa.org/assets/documents/nwgs/debris-in-brief-factsheet.pdf .