"High Temperature"? I wouldn't call 55K a very warm temp at all. Although, this is a significant break through in getting a material closer to "at room temp" superconducting. They need to get to the range of 273-310K before it will be of widespread feasibility to use. However, a 55K superconductor would be useful in several spaceflight applications. This might lead to the development of a new propulsion system or much more powerful ion drives.