A current Orion design would have the advantage of another 40 years of nuclear weapons research. I suspect small, high efficiency nukes are available. Also, the radiation channel of the directed energy nuke can be filled with boron to absorb the nasties. Even with the weapons available in the 50s and 60s, radiation release during launch was expected to be less (much less) than a large fusion weapon test in the atmosphere.<br /><br />The nukes for even a (seemingly) large Orion craft are smaller than the Hiroshima device in yield.<br /><br />Really large Orion craft could be assembled in orbit (lunar perhaps) and then could be launched from there. Solar wind will dissipate the radiation from the bigger nukes from the space launched craft.<br /><br /><br />BTW, a possible challenge to launching an Orion craft from earth's surface, the fireball engulfment of the vehicle from the first few detonations, may have an easy solution.<br /><br />And no, I'm not going to tell you what it is, but its very clever, nearly existing technology, and light weight. Arthur Clarke would recognize it.<br /><br /><img src="/images/icons/wink.gif" /><br /><br /><br /> <div class="Discussion_UserSignature"> <p><font color="#ff0000"><strong>TPTB went to Dallas and all I got was Plucked !!</strong></font></p><p><font color="#339966"><strong>So many people, so few recipes !!</strong></font></p><p><font color="#0000ff"><strong>Let's clean up this stinkhole !!</strong></font> </p> </div>