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wellerstein's profile
Alex Wellerstein
Alex Wellerstein
Alex Wellerstein
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@wellerstein

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Alex WellersteinVerified account

@wellerstein

Historian of science, secrecy, and nuclear weapons. Professor of STS at @FollowStevens. UC Berkeley alum with a Harvard PhD. NUKEMAP creator. Coder and web dev.

Hoboken, NJ / NYC
blog.nuclearsecrecy.com
Joined September 2011

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    1. Kristian Harstad‏ @KristianHarstad 28 Jul 2017
      • Report Tweet

      Kristian Harstad Retweeted Alex Wellerstein

      Are you confusing circular error probable with single shot probability of kill?...https://twitter.com/wellerstein/status/890999430366756864 …

      Kristian Harstad added,

      Alex WellersteinVerified account @wellerstein
      Replying to @NuclearAnthro @nktpnd and 3 others
      It depends what your imagined target is, whether it is small and hard or large and soft — e.g., military base vs. city. 1/2
      2 replies 0 retweets 0 likes
    2. Alex Wellerstein‏Verified account @wellerstein 28 Jul 2017
      • Report Tweet
      Replying to @KristianHarstad

      No. SSPK is derived from CEP. With a soft target the size of, say, Los Angeles, your SSPK approaches 1 no matter what your yield.

      1 reply 0 retweets 0 likes
    3. Kristian Harstad‏ @KristianHarstad 28 Jul 2017
      • Report Tweet
      Replying to @wellerstein

      But you talked about CEP, not SSPK. CEP is radius within which missile lands 50% of time. Nothing to do with target hardness!

      1 reply 0 retweets 0 likes
    4. Kristian Harstad‏ @KristianHarstad 28 Jul 2017
      • Report Tweet
      Replying to @KristianHarstad @wellerstein

      CEP is, essentially, a measure of a missile's precision - not of its efficacy against target once hit.

      5 replies 0 retweets 0 likes
      Alex Wellerstein‏Verified account @wellerstein 28 Jul 2017
      • Report Tweet
      Replying to @KristianHarstad

      Smallness/hardness of target relates to how much PSI you need to destroy. For soft target, 5 psi will do.

      2:11 PM - 28 Jul 2017
      1 reply 0 retweets 0 likes
        1. Kristian Harstad‏ @KristianHarstad 28 Jul 2017
          • Report Tweet
          Replying to @wellerstein

          That is about probability of kill, not CEP. CEP is about precision of targeting, not effectiveness of hit.

          0 replies 0 retweets 0 likes
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