Have you considered
looking up element 115 on
Wikipedia? If you had, you would have found an entry for
Ununpentium.
Whether or not an elment is viable has nothing to do with its galaxy. Rather, it has everything to do with its nuclear/atomic/molecular structure.
As for "anti-gravity emitters and such," references to those sorts of things belongs in the ATM (Against the Mainstream) section.
Welcome to the board, consider looking at the links I provided, and have fun!
By the way, I answered "YES," as it's viable for 87.5 ms for isotope 288, and 32 ms for isotope 287.