Nexus

Field Emission Electric Propulsion (FEEP) is a type of electric propulsion that uses electrostatic fields to extract and accelerate ions from a liquid metal propellant, producing thrust. It is known for its extremely precise thrust control, making it ideal for applications that require high-precision positioning in space.

How it works:

1. Liquid Metal Propellant – uses low-melting-point metals like Cesium or Indium as fuel
2. Electrostatic Extraction – a sharp metal emitter is charged to a high voltage forming a strong electric field
3. Ion Emission – the field is strong enough to extract individual metal ions from the liquid surface, forming an ion beam
4. Acceleration – these charged particles are accelerated to high velocities by the electric field to generate thrust
5. Charge Neutralization – an external electron source (neutralizer) ensures the spacecraft remains electrically neutral

Key Differences between FEEP and electrospray are:

Key Differences between FEEP and HET are:

Indium (In) is a soft, silvery-white metal with atomic number 49. It is commonly used in electronics, semiconductors, and coatings due to its excellent conductivity. Indium is non-toxic, nonreactive and nonradioactive, making it a safe and easy to handle.

INDIUM HAS SEVERAL IMPORTANT ADVANTAGES AS A PROPELLANT:

• It is compact due to its higher density — The graph above presents a comparison of tank sizes between the ENPULSION MICRO and a Hall-Effect thruster (operating at 1 200 s ISP @ 100 w) of same total impulse using different propellants.
• Thrusters are shipped full — Propulsion systems using other propellants usually have to be shipped empty and filled at the launch facility, introducing additional expenses and procedures.
• It is safe — Indium is non-toxic and easier to handle than other propellants. It is stored, unpressurized and, unlike high pressure tanks, it does not need special authorizations (launch waivers) to be launched as secondary payloads, and is RoHS and REACH compliant.
• It is readily available — Indium is currently a by-product of zinc refining and benefits from industrial scale production. Since peaking at $700 / kg in 2007 indium prices have stayed below $400 / kg.

FEEP thrusters can be used for precise spacecraft maneuvers, including station-keeping, orbit raising, formation flying, collision avoidance, and drag compensation. Their high precision and controllability make them ideal for missions requiring fine attitude adjustments.

Most electric propulsion systems operate at a fixed power point, so they are typically characterized by a single thrust and specific impulse value. FEEP thrusters are different. They operate across a wide power range, and as a result, both thrust and specific impulse vary with input power.

This is why the data sheet shows a curve rather than a single point. As power increases, thrust and Isp both change, and not always in a linear way. Higher power generally produces more thrust and higher Isp, but the relationship depends on how the thruster is tuned.

This flexibility allows the system to adapt performance to the mission. You can operate it more efficiently when needed or increase thrust for faster maneuvers. The performance curve captures this range of operating modes.

Yes, our products are classified as “dual-use” items and as such are subject to dual-use export controls. Therefore, depending on the end-use and country of destination, an export license may be required. Deliveries within the European Union and the United States generally do not require an export license.

No, all our products are ITAR-free.

ENPULSION offers some of the fastest lead times in the satellite propulsion industry. Our standard delivery times vary by product and model type:

ENPULSION NANO LARK

Flight hardware: 30 weeks typical (can be reduced to 24 weeks with an express fee)

Engineering or qualification models (EMs/EQMs): 24 weeks typical (can be reduced to 12 weeks with an express fee)

ENPULSION MICRO STARLING

Flight hardware: 30 weeks typical (can be reduced to 24 weeks with an express fee)

Engineering or qualification models (EMs/EQMs): 24 weeks typical (can be reduced to 12 weeks with an express fee)

Additional Notes:

ENPULSION lead times are significantly shorter than many other satellite propulsion systems, reflecting our streamlined production and in-house manufacturing capabilities

In select high-priority cases, ultra-accelerated lead times of one month or less may be possible; these are handled on a case-by-case basis and are not part of our standard offering

Larger or recurring orders may qualify for favorable terms, including reserved production slots, optimized delivery scheduling, or volume pricing based on planning visibility and contract structure