Observing Celestial Superfluids

Even in 1913 Kamerlingh Onnes envisioned the use of superconductors to create powerful magnetic fields well beyond the capability provided by cooling normal metals with liquid helium.  Only some “bad places” in his Hg and Pb wires seemed to impede his first attempts at this dream, one of course that required another 50 years in which a true understanding of the difference between type I and type II superconductors and the discovery of compounds such as Nb3Sn that could remain superconducting to fields as high as 30 T had to occur. In the last 45 years virtually all superconducting magnets have been made from just two Nb-base materials, Nb-Ti and Nb3Sn.  Now it seems that a new generation based on cuprates with fields well above 30 T may be possible with the cuprates based on Bi-Sr-Ca-Cu-O and the RE-Ba-Cu-O compounds.  The application potential of superconducting magnets will be discussed