The Nyota propulsion system is the most widespread propulsion system in the Zambarau Concord. The Zambarau Concord does not posess faster-than-light propulsion technology and the general consensus is that superluminal travel is impractical or impossible, so little research goes into this field. For this reason Nyota propulsion dominates not just interplanetary, but interstellar travel. Nyota propulsion is favoured because of its simplicity and the fact that it does not take much accuracy to build (relatively speaking) but sometimes loses out to alternate propulsion systems because of its reliance on antimatter.
Nyota propulsion systems use antimatter-catalysed fusion but the engineering is deceptively simple. The centre of a Nyota engine is the Nyota itself; this is a specially crafted beryllium container which can take many shapes; some are spherical but many are fat discs (this is for many reasons, including exhaust direction and heat dissipation). Because of the atomic structure of the beryllium container particles travelling at a sufficient velocity pass through as if it were not there at all.
The Nyota is filled with fuel; this is usually protium seeded with a carbon catalyst, though some versions use different combinations such as deuterium or deuterium and helium-3 to increase thrust, as well as protium with either lithium-7 or boron-11 for low-radiation versions. During operation a small particle accelerator fires antiprotons at the Nyota at over 750km/s; this induces extremely energetic fusion reactions ('Nyota' directly translates to 'star') which give off high energy charged (though some fuel mixes also release neutrons) particles that pass out of the Nyota.
These particles are then redirected by magnetic fields within the engine into an exhaust stream; this process is nearly 100% efficient, as charged particles travelling in the wrong direction are slowed down by magnets, which gives energy to the magnets via induction; this energy is then used in re-accelerating the particles in the correct direction.
Nyota engines are surprisingly efficient in their use of antimatter. With an exhaust velocity of 0.117c (35,100km/s), only 10 milligrams of antimatter is required for each tonne of fuel. This efficiency is essential for making Nyota propulsion viable; antimatter production systems in the Zambarau Concord use Schwinger pair creation and are less than 1% efficient in their conversion of energy to matter/antimatter. A general antimatter factory in the Concord will produce about a kilogram of antimatter per year; antimatter factories are powered by either solar power or electrostatic fusion reactors.
A typical starship employing Nyota propulsion has a mass ratio of 20 and employs a magnetic 'parachute' (which reacts against the interstellar medium) to decelerate at the end of its journey. With an exhaust velocity of 0.117c, the cruising velocity of these starships is about a third of lightspeed, allowing a starship to cross from one side of the Zambarau Concord to the other in just over 80 years.
There has been ongoing research into a Nyota engine that is not reliant on antimatter. This mainly involves firing high-energy protons into the Nyota instead of antiprotons; however, there are significant problems with this design. While the antiprotons need only be accelerated to 750km/s, a proton must be accelerated to 96.4% lightspeed to give the same energy as a proton-antiproton annihilation; at these velocities most of the protons pass straight through the Nyota without causing any fusion reactions (or at least get deflected without transferring all of their energy).