I have a ‘strong suspicion’ that there may be more to these two phenomenons than we would want to think. :-]
From Adams post
Seems the USAF want to put nukes on UAVs and UCAVs to give them several MONTHs of flight time...
http://www.newscientist.com/news/news.jsp?id=ns99993406
...according to the article they won't use RTGs or nuclear reactors [how could you fit one in a UAV???] Instead they'll be using an x-ray pumped Hafnium reactor - something very surprising when I read it. Apparently some researchers discovered the reaction in 1999. Hafnium 178 [a fission by-product???] hit by x-rays puts out up to 60 times the energy put into it as its isotopes undergo nuclear transitions and release gamma-rays.
The USAF think it's safer than standard nukes since the reaction needs the x-rays to release energy and Hafnium 178 isn't a nasty radioactive. If it's feasible it will enable their plans for very long-duration UAVs.
I wonder how much Hafnium 178 is lying around?
Could be an easier way to make nuclear rockets? Replace RTGs?
From Phil’s earlier post
A GRB is the most energetic event known in the universe outside of the Big Bang.
It MAY be a special type of Supernova exploding star and it may not. A GRB could sterilize an entire galaxy or a local group of galaxies were its energy radiated in all directions. Fortunately, recent evidence says that it's NOT omnidirectional, instead a beam of energy, gamma rays then particles is emitted. Like a flashlight beam it's narrow. Just don't be in the way. One of these may go off in the local group of galaxies every say 200 million years. It's OK as long as you're not in the beam's path.
What if every 200 million years or so, some alien civilization figures out how to construct a very powerful gamma ray laser and is using it to propel their ‘large’ spacecraft.
Now imagine what would happen if they would come over here and would say that we should stop arguing with each other, I think we should listen :-)
Cheers
Johannes