> I can't believe he actually thinks it would be safer to launch a rocket which if it has an issue will explode with the energy of a nuclear weapon as compared to one with a nuclear reactor which will crash and spread a small amount of radioactive material
It *would* be safer, in many ways. If you launch your antimatter rocket out in the middle of nowhere, like, say, off a floating platform in the ocean, if things go wrong theres a flash and that's the end of it. If the payload is a nuclear reactor, though, you have at least the potential for the uranium to be vaporized and create uranium oxide hazards downwind.
The antimatter system has good potential for use as a launch vehicle propulsion system, operating from the pad to orbit and beyond. Nukes don't really have that potential.
> How do you confine these anti-matter particles in large numbers and how do you create them economically. Reading the article, it would seem like it this a minor issue.
Creating and storing cryogenic liquid hydrogen was once an issue.
I don't know if the astronauts would consider it safer! 10 milligrams is equivalent to 500 tons of TNT. And if that's not bad enough, the exposure from the gammas would unquestionably be fatal. At least with a chemical rocket you theoretically have a chance to get away from a dangerous rocket with an escape mechanism (like on the Apollo program).
I think you overestimate the danger with a nuclear reactor. Nuclear reactors don't suddenly explode and vaporize everything (especially their fuel). And even if they did, you could apply your caveat of being in the middle of the ocean. Any way you look at it (unless you have accumulated significant radioactive material in the reactor core), the nuclear option is safer. The nuclear option will only be dangerous if you take active measures to make it that way (violate safeguards, etc). The antimatter option is only *safe* if you take active measures to make it that way (ensure confinement).