User blog comment:WolfKingDemon/Gas properties for orion/@comment-27404954-20160703231421

Copy-pasting from Wikipedia? How cute. But yeah, you're still wrong. Even ortho hydrogen is nowhere near as powerful as antimatter, as antimatter and matter annihilate completely, thereby releasing all energy within the two substances. Ortho hydrogen, on the other hand, still must undergo a reaction to be usable as thrust -- and that's disregarding the process you need to go through to get ortho hydrogen.

Sorry, but no. You're scientifically incorrect and your post is therefore invalid.