Call me cray cray, but you may have to check your calculations again... To make up for the totally impenetrable yet incredibly unstable neutronium, the Traveler has something inside not mentioned in the lore, yet... A small core made of element 117. The magic numbers of neutron and proton in 117 and its properties (still unknown to us at the present time) would create a small island of stability inside the Traveler. Also bismuth, not mentioned in the lore, might be another component of the outer core because of its electrocatalyst properties. It also could explain the faint iridescence on the Traveler's surface which seems sometimes unrelated to the surrounding light. [spoiler]Should you need me to shed more light *HaHaHaHaHaHa* on these hypothesis,, I'll be in the back of the room, drawing evil bunnies.[/spoiler]