these sparse, art-like images show the Kholod scramjet – a Russian-built prototype air vehicle that reached Mach 6.47 back in the late 90s – making it the fastest machine to fly within the Earth's atmosphere. part of a joint programme between the Russian Institute for New Propellants (CIAM) and NASA, the Kholod series was carried aloft aboard a modified surface-to-air missile before launching and switching to supercooled liquid hydrogen. one of the systems (complete with missile, engine and display stands) is up for auction this September if you're looking for a nice loft centrepiece