The ultradense core of an exploded star contains a bizarre form of superconducting matter called a superfluid, new studies suggest. Superfluids made of charged particles are also superconductors, which allow electric current to flow with no resistance. Superfluidity is a friction-free state of matter, and superfluids created in labs here on Earth exhibit remarkable properties. It can climb upward, for example, and escape airtight containers, researchers said. The matter, found by researchers using NASA’s Chandra X-ray Observatory, is at the core of Cassiopeia A, the remains of a massive star that exploded in a supernova.