A spacecraft propulsion engineer has built a striking desktop display using noble gas tubes, inspired by their work with Xenon ion thrusters. The project, dubbed the "Crown of Nobles," combines five different noble gases - Helium, Neon, Argon, Krypton, and Xenon - in a custom 3D-printed stand powered by a repurposed plasma ball base.

The engineer wanted hands-on experience with ionized gases after working with Xenon fuel in abstract metal cylinders for satellite propulsion. While commercial gas tubes are available, finding a suitable display mount proved challenging, leading to the DIY solution. The display uses capacitive coupling through aluminum foil caps to ionize the gases, with a rotary switch allowing users to cycle between different elements.

The project demonstrates interesting physics principles, with Neon being the easiest gas to ionize despite Xenon having the lowest ionization energy. The setup creates significant RF interference, sometimes causing heavier gases like Xenon to require manual encouragement to light up. The engineer emphasizes safety precautions when working with high-voltage components and notes that the display serves both as an educational tool and a conversation piece for those interested in plasma physics and space propulsion technology.