**6.4 Annihilation chamber**

The annihilation chamber (or the "interaction chamber" in **Figures 7** and **9**) is where the electrons and positrons will collide and annihilate. It is where the gamma rays will be produced to propel the entire spaceship.

The annihilation chamber will, at least on its inside, be somewhat bell-shaped, although probably flatter. The shape is similar to the rocket nozzles that are used on chemical rockets. **Figure 10** highlights a cutaway of the interaction chamber, where matter/anti-matter annihilation will take place.

### **6.5 Interstellar probes**

Probes to nearby stars will probably not require a storage system. Instead, the electrons and positrons created in the generator will probably be directed immediately to the annihilation chamber, where they will annihilate and propel the craft. The highest speeds are achievable when a mission, like an unmanned interstellar mission, has a low spacecraft weight and an extended time to travel.

The annihilation chamber will also be the probes' primary tool of stearing. In order to stay on target, moveable panels in the annihilation chamber will likely asymmetrically direct the gamma-ray "exhaust" to stear the probe.

**Figure 10.**

*Cutaway of annihilation chamber, or "interaction chamber" (courtesy Mustang Publishing).*

## **6.6 Launch environment**

The best launch environment for matter/anti-matter spacecraft is probably the Moon. With no atmosphere, the matter/anti-matter annihilations will be better controlled. The lower mass of the Moon permits faster launch acceleration. Furthermore, it is likely that chemical booster rockets will aid the initial launch of a matter/anti-matter spacecraft, in order to achieve maximum initial acceleration, somewhat like the solidpropellant rocket boosters of the United States' Space Shuttle and Artemis rocket. The United States' current Artemis Project would be well-suited to build the infrastructure and to ferry the components and materials for launch of an interstellar probe.
