What happens when a jet-engine engineer looks beyond the atmosphere and applies the logic of aerospace engineering to the mysteries of space? In Alien Physics: Space Explained by a Jet-Engine Engineer, Adrian Caldwell takes readers on an unconventional journey through the cosmos—one guided not only by astronomy, but by the instincts of an engineer accustomed to thinking in terms of heat, pressure, materials, vibration, energy, failure, and survival. From interstellar objects travelling on hyperbolic trajectories to strange Martian formations, exploding stars, cometary plumes, cosmic radiation, orbital mechanics, and the unforgiving physics of vacuum, Caldwell asks a fascinating question: Can the engineering principles we use to understand machines help us see the universe differently? A comet releasing gas into space begins to resemble a nozzle operating without walls. Orbital perturbations invite comparisons with rotating machinery and dynamic systems. Spacecraft materials face thermal and structural challenges that echo those encountered inside high-performance engines. Noisy astronomical observations raise the same fundamental problem engineers encounter in test cells: how do we distinguish a genuine signal from misleading data? Drawing on the language and intuition of aerospace engineering, Alien Physics makes complex ideas tangible without reducing the wonder behind them. This is not a conventional astronomy textbook, nor an attempt to replace astronomy with engineering. It is an engineer’s way of looking up: finding familiar physical principles operating on scales almost beyond imagination. For readers fascinated by space, aviation, physics, engineering, and the machinery of the universe, Alien Physics offers a new way to understand the sky—and perhaps a new reason to keep looking up.