Do you think that its plausible that intelligent life could develop and advance to the point of space travel, especially interstellar space travel without having access to fission-able materials and/or having discovered fission?
It seems unlikely to me as the methods I've heard for creating an energy rich fuel source seem to require knowledge of atoms and their components. Seems to me that they would certainly know about fission. And it seems unlikely to me that a planet would have enough variety of elements for the complex molecules needed to create life while somehow not having any access to fissionable materials.
But I don't know and I'd like to hear a more educated opinion.
This is something that's hard to call given that we as a society haven't actually developed any solid forms of space travel. The space travel we have accomplished has, to my knowledge, used chemical fuels, which can be developed and used effectively without knowledge of nuclear fission.
KingDragonlord, just for sake of precision, I was jumping a gun a bit when I said nothing bellow iron. There are a few elements there that are heavy enough to require just "a bit" of extra energy. So you can hit them with a neutron that's going just fast enough not to blast them apart, yet transfer enough energy in for the nucleus to become unstable. We are still talking about a neutron traveling very near the speed of light, requiring an accelerator, and impacts being just on the threshold of "shattering" the nucleus.