Last week researchers from Purdue and Penn State University launched a rocket that uses an unconventional propellant: aluminum-ice. The fuel mix, dubbed ALICE, is made of nano-aluminum powder and frozen water, and gets its thrust from the chemical reaction between the ingredients. The propellant is environmentally friendly, and it could perhaps allow spacecraft to refuel at locations like the moon, where water has been discovered.
Using aluminum for fuel is not completely new–the space shuttle’s solid rocket boosters use a small amount of the metal, as will NASA’s Ares rocket. But the new work involves making aluminum one of the key ingredients by using nanoscale particles. These tiny particles, when ignited, combust more rapidly than larger particles, forcing more exhaust gases out of the metal and giving the rocket the necessary kick.
The oxygen and hydrogen in water molecules enhance the combustion of the aluminum. Freezing the propellant keeps it intact, avoiding any premature reactions.
The propellant was able to lift a rocket 396 meters during an August flight test, which was funded by NASA and the Air Force Office of Scientific Research. Now, for even better performance, the researchers are working on adjusting the ratios of different ingredients and possibly mixing the nano-aluminum with larger aluminum particles.
A water-based propellant might one day mean that spacecraft could carry less fuel when traveling to distant locations like the moon or even mars. But it would also be nice to have a “greener” fuel for rocket launches back on Earth.
This new data poisoning tool lets artists fight back against generative AI
The tool, called Nightshade, messes up training data in ways that could cause serious damage to image-generating AI models.
The Biggest Questions: What is death?
New neuroscience is challenging our understanding of the dying process—bringing opportunities for the living.
Rogue superintelligence and merging with machines: Inside the mind of OpenAI’s chief scientist
An exclusive conversation with Ilya Sutskever on his fears for the future of AI and why they’ve made him change the focus of his life’s work.
How to fix the internet
If we want online discourse to improve, we need to move beyond the big platforms.
Get the latest updates from
MIT Technology Review
Discover special offers, top stories, upcoming events, and more.