Torch Drives
Propulsion Technology
Advanced propulsion systems for spacecraft
- Metallic Hydrogen Engines
- Magnetic Target Fusion Engines
- Daedalus Engines
- Bussard Ramjets
Long-duration high-speed space travel between planets and stars
Various engineered solid, plasma, and magnetic systems
Technological constructs; visible
Yes
Contained within spacecraft designs
Varies from vessel-sized to larger starships
Human and alien scientific advancements
Ongoing technological usage and refinement
Engineered for long-term high-stress operation
Extended acceleration, relativistic travel capability
Enables humanity and other species to explore and colonize distant worlds
Engine containment failure, fusion hazards, relativistic travel risks
Developed from the need for efficient interplanetary and interstellar travel
Near-future scientific development following chemical rocketry
To traverse the great distances between planets and stars, many methods of propulsion have been created to aid large scale transportation and exploration. In order to get between celestial bodies separated by great distances, engines that can burn for days or months - torch drives - have been created to allow spacecraft to accelerate to several hundreds, thousands and hundreds of thousands of kilometers a second. Without these engines, the stars would be separated by hundreds of thousands of years of travel time.
Metallic hydrogen
After liquid fuel and oxidizer came metallic hydrogen, a light and energetic fuel providing much higher specific impulse than a typical rocket engine. Working in the atmosphere and in the cold depths of space, the metallic hydrogen rocket makes a great propulsion method for exploration vessels and surface -> space cargo lifters.
Magnetic Target Fusion
The Magnetic Target Fusion Engine is a light weight and highly efficient successor to the Orion engine, using lasers to squeeze fusion pellets. Magnetic fields are used to confine the fusion fuel and act as a pusher plate to prevent sudden acceleration. The result is a relatively high thrust and an extremely high specific impulse.
Daedalus
The Daedalus engine was one of the earliest torch drives created. Using electron beams to inertially confine fusion pellets and a magnetic nozzle to direct the exhaust, it can accelerate spacecraft to several percent of the speed of light and even slow down. Daedalus craft often have their crew reproduce or be put into suspended animation due to the several decade long transit times posed by the distance between even the closest stars.
Bussard Ramjet
The next breakthrough after the Daedalus engine was the Bussard Ramjet. The Bussard ramjet uses a ramscoop that uses a magnetic field to collect interstellar hydrogen from the vast regions of space between planets and stars, and compress it with said magnetic field until fusion occurs. The drive then directs the exhaust using yet another magnetic field, all of this resulting in an engine with an infinite burn time. However, all that hydrogen, much like in a very thin atmosphere, results in drag that prevents a Bussard Ramjet from exceeding 1/3rd the speed of light.