Apollo Fusion has been awarded an exclusive worldwide commercial license by NASA's Jet Propulsion Laboratory (JPL) for its MaSMi (Magnetically Shielded Miniature) Hall thruster, the world's first low-power (≤1.0 kW) unit. MaSMi has demonstrated performance with a peak total efficiency of 54%, a peak total specific impulse of 1940s, and an estimated throughput capability of >150 kg Xe. MaSMi is a key component of JPL's ASTRAEUS (Ascendant Sub-kW Transcelestial Electric Propulsion System), a low-power electric propulsion (EP) system optimised for use on smallsats. In support of ASTRAEUS, Apollo was awarded a contract to manufacture three engineering model MaSMi-EM thrusters for JPL this summer.
Apollo is also designing a commercial version of this thruster called AXE (Apollo Xenon Engine) following an internal design-for-manufacturing process. The design-for-manufacturing improvements will enable AXE to be rapidly mass-manufactured for large constellation customers.
Apollo CEO Mike Cassidy noted, "We're absolutely thrilled to be working with NASA JPL and with Dr Ryan Conversano, the inventor of MaSMi. The MaSMi thruster that we now have the exclusive license for can produce more than 2,000,000 N‑s of total impulse and yet is about the size of a soda can. We've heard many times that our propulsion system's high performance coupled with our rapid, high-volume manufacturing is enabling new space missions and constellations. This new relationship with NASA JPL further demonstrates that Apollo can deliver for these new constellations."
In addition to the NASA JPL thruster that Apollo has licensed, the smaller Apollo Constellation Engine (ACE) provides this performance at 400 watts: 24 mN of thrust, 200,000 kN-s of total impulse, at 4.5 kg of dry mass. This is about three times the total impulse per unit mass of any competitive propulsion system and about three times the total impulse per unit volume of any competitive propulsion system on the market for 50kg-500kg smallsats.