Orbital Arc is a stealth-mode electric propulsion startup.  We are developing a new variety of ion thruster using a patent-pending ionization technology that produces ions ~4x as efficiently as competing Hall Effect and gridded ion thrusters. 

The added efficiency gives our thrusters energy headroom to operate at higher thrust than competitors in low-power regimes, and higher ISP when power is available. This results in a flexible, scalable, modular thruster that fits on a cubesat but is adaptable  for missions ranging from LEO to interplanetary. Theoretically, the exhaust velocity can reach a few percent of light speed; while our prototype will not achieve this level, we still think the theory justifies the name: Relativistic Ion Thrust Drive, or RIOT Drive for short.

Our ionization method is also so gentle that it typically will not break molecular bonds, allowing our thruster to use compound molecular fuels, including effectively any gas-phase propellant (such as unaltered air). Our favorite fuel option, though, is Sulfur Hexafluoride, which is non-toxic, non-corrosive, and has a higher molecular weight than Xenon at less than 1% of the cost.