space security


Don’t Scapegoat China for Killing the INF Treaty. Ask it to Join.

, China project manager and senior analyst

September 23, 2016: Chinese UN Representative Liu Jieyi votes in favor of a UN Security Council resolution on the 20th anniversary of the signing of the Comprehensive Test Ban Treaty (CTBT) urging all parties to push for the treaty’s entry into force.

The Trump administration recently announced it intends to walk away from an important agreement that reduces the risk of nuclear war—the INF Treaty. US officials said concerns about China were an important factor in deciding to scrap a nuclear arms control pact intended to last in perpetuity. But there is no evidence the Trump administration consulted Chinese leaders about its plans to withdraw or the concerns that supposedly made it necessary. Read more >

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Record Number of Satellites in Orbit

, senior scientist

An updated version of the UCS Satellite Database has been posted. Including launches and deactivations through November 30, 2018, the Database includes information on about 1,957 active satellites. That is 71 more than our previous release last July. Read more >

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24 Space-Based Missile Defense Satellites Cannot Defend Against ICBMs

, co-director and senior scientist

UPDATE: In September 2018, UCS released an animated feature and video that explains how space-based missile defense works. Check it out here.

Articles citing a classified 2011 report by the Institute for Defense Analysis (IDA) have mistakenly suggested the report finds that a constellation of only 24 satellites can be used for space-based boost-phase missile defense. Read More

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Questions about a US Space Force

, senior scientist

This week, President Trump verbally directed General Dunford, the Chairman of the Joint Chiefs of Staff, “to begin the process necessary to establish a Space Force as the sixth branch of the armed forces.”

The term “Space Force” really got everyone’s attention. Obviously, everyone wants to know what the uniform would be. And the whole idea is built for memes.

What’s it all about? Let me respond to three different kinds of questions I’ve been hearing about this. Read more >

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Tillerson, Mattis and the Chinese

, China project manager and senior analyst

Rex Tillerson and James Mattis are talking to their Chinese counterparts. The conversation is just getting started but it appears to be constructive. Their remarks to the press after a recent meeting in Washington with State Councilor Yang Jiechi and General Fang Fenghui should calm Asian fears about potentially destabilizing changes to US policy in the region. Read more >

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