Current rocket technology uses the oxidation of chemicals to produce what might be a controlled, slow-motion explosion. That explosion is directed through rocket engine nozzles to achieve thrust. The challenge of scaling up the power requires ever bigger and heavier engines, and tons more fuel/oxidizer.
NASA’s biggest rocket until now was Saturn V, used to send humans to the Moon. Now NASA has developed the SLS (Space Launch System) for our return to the Moon. Space-X is working on its Starship, a vehicle beyond its Falcon Heavy booster. They all share the same basic technology, that of the Saturn V and most every rocket used for human space exploration to date.
While those rockets will ultimately be used for trips to the Moon (NASA’s Artemis Program), a new rocket technology is in development for future use in lunar and solar system exploration. And it’s a doozey!
Imagine if you will, a Rotating Detonation Rocket Engine (RDRE). My first visual is of a Gattling Gun. Can you imagine sitting atop a Gattling Gun while it blasts away below? OK, it’s not a Gattling Gun but the visual is kind of valid, only not. RDRE technology exploits the characteristics of supersonic combustion detonation. Under extreme pressures, and supersonic speed, fuel will detonate and create tremendous pressure waves. When these pressure waves are developed in a circular chamber they spin around while exiting, producing more power per fuel unit than conventional rockets.
NASA’s RDRE is something that has been in planning for a long time, but only recently has materials technology advanced enough to test it properly. Previous materials would degrade quickly. New materials developed at NASA allow for extreme pressure and temperature without overheating. The new alloy is copper based, with chromium and niobium added, called GRCop-42. This alloy has high strength, heat dispersion, and high conductivity. It retains its strength at extremely high temperatures. That’s good. The rocket engines are made using powder bed fusion additive manufacturing (3D printing) to boot, another innovation that will lead to improved results.
So far, NASA and its partner IN Space LLC has tested an engine producing 4,000 pounds of thrust at an average chamber pressure of 622 pounds per square inch. It’s more a proof of concept than a useable engine, but it worked flawlessly so scaling up to a 10,000+ pound class engine is expected. Now we’re talking Moon shots and solar system exploration. With its lighter fuel weight needs and higher efficiency, RDRE capable of acceleration to 50,000+ miles per hour are within reach, making trips to planet a lot shorter. Less reliance on swings around the Earth and/or Venus to get enough speed for a trip to Jupiter, eh?
Not a Gattling Gun, but just as cool.
What’s in the Sky?
August 24, an hour after sunset, south-southwest: A waxing gibbous Moon sidles up to bright star Antares in Scorpius. If you have a telescope or even binoculars, start earlier and watch carefully. You might be able to see the Moon cover globular cluster M4 before it gets ever closer to, even covering Antares.