Apollo Constellation Engine
Apollo Fusion (Astra)
ACE is a compact Hall-effect thruster propulsion system developed by Apollo Fusion (acquired by Astra in 2021) for smallsat and constellation electric propulsion, offering multi-propellant (krypton or xenon) operation at 400 W.
Typed specifications54 values
Discloses 8 of 10 fields engineers filter by in this category (category median 3).
- Propulsion family
- electric datasheet p.1
- Mass
- 1.5 kg PPU mass · datasheet p.3 1 kg thruster mass | 1 kg THRUSTER, KRYPTON | 1 kg THRUSTER, XENON | 7.6 kg TOTAL DRY MASS, example single string krypton configuration w…
- Thrust
- 18 mN krypton (~) · datasheet p.1 25 mN xenon (~) | 18 mN krypton | 25 mN xenon
- Specific impulse
- 1 300 s krypton (~) · datasheet p.1 1 400 s xenon (~) | 1 300 s krypton | 1 400 s xenon
- Total impulse
- 200 000 N·s krypton · datasheet p.1 300 000 N·s xenon | 200 000 N·s krypton | 300 000 N·s xenon
- Propellant
- krypton datasheet p.1 xenon
- Supply voltage
- 28 V nom. · PPU input · datasheet p.3 28 V unregulated input | 27–34 V inclusive, PRIMARY | 27–34 V primary input, inclusive | 27–34 V primary, krypton +3
- Power consumption
- 400 W krypton · datasheet p.2 20 W PPU dissipation | 4 W thruster dissipation | 400 W xenon
- Data interface
- RS-485 datasheet p.5 CAN
- Operating temperature
- -20–60 °C datasheet p.6
- Radiation tolerance (TID)
- 25 krad PPU design · datasheet p.3 25 krad target for parts level testing
- Thruster technology
- Hall effect datasheet p.1
- Tank volume
- 3 L example single string krypton configuration · datasheet p.6
- Feed / tank pressure
- 275.79 bar high pressure side, MEOP, 60 °C · datasheet p.4 186.16 bar MEOP, 60 °C | 275.79 bar MEOP, 60 °C, option | 275.79 bar max · MEOP high pressure side at 60 °C | 186.16 bar max · tank MEOP at 60 °C (option 4,000 psia)
- Power at thrust
- 400 W input power, krypton and xenon · datasheet p.1
- Survival temperature
- -30–70 °C qualification/survivable test temperature · datasheet p.6
- Flight heritage
- Selected by York Space Systems for a 10+ satellite LEO constellation (2022); used on Spaceflight Inc. Sherpa-LTE orbital transfer vehicle; multiple on-orbit flights since ~2021 as Astra Spacecraft Engine; ground tested to 12,000+ cycles product page
- Power processing unit included
- yes single board PPU · datasheet p.1
- Dry mass
- 7.6 kg example single string krypton configuration with 3 L tank · datasheet p.6
- Ignition or start
- other high voltage igniter; heaterless instant-start cathode · datasheet p.3
- PPU output power
- 400 W datasheet p.2 280–600 W | 300–500 000 W
- PPU efficiency
- 95 % datasheet p.3
Each value is typed with its unit and measurement condition and cites the datasheet page it was taken from. Nothing is guessed: a field that is absent here has not been published by the manufacturer. machine-extracted ✓ checked by NewSpace Market ✓ manufacturer confirmed by the manufacturer.
As published by the supplier11 lines, in the manufacturer's own wording
- Thruster type
- Hall-effect thruster
- Propellant
- Krypton, Xenon, or proprietary propellants (multi-propellant capable)
- Input power
- 400 W (operable 280-600 W)
- Thrust (Krypton)
- ~18 mN
- Thrust (Xenon)
- ~25 mN
- Specific impulse (Krypton)
- ~1,300 s
- Specific impulse (Xenon)
- ~1,400 s
- Thruster mass
- 1.0 kg
- PPU efficiency
- 95%
- Radiation tolerance
- Radiation-tolerant PPU >20 kRad (LEO, 5-year life); radiation-hardened PPU >50 kRad (up to GEO, 15-year life)
- Flight heritage
- Selected by York Space Systems for a 10+ satellite LEO constellation (2022); used on Spaceflight Inc. Sherpa-LTE orbital transfer vehicle; multiple on-orbit flights since ~2021 as Astra Spacecraft Engine; ground tested to 12,000+ cycles
About
The Apollo Constellation Engine (ACE) is a clean-sheet Hall-effect thruster propulsion system built by Apollo Fusion, a spacecraft propulsion company acquired by launch and space systems company Astra in 2021. ACE is designed for satellite orbit-raising, station-keeping, deorbit, and constellation deployment, targeting the growing market of LEO smallsat constellations and GEO/cislunar spacecraft. Its innovations include multi-propellant capability with krypton, xenon, or proprietary propellants, a heaterless center-mounted instant-start cathode, novel magnetic lensing and magnetic circuit, and a 95%-efficient single-board radiation-tolerant power processing unit. The thruster (~1.0 kg) has been ground tested from 280 W to 600 W and is baselined at 400 W, delivering ~18 mN thrust and ~1,300 s Isp on krypton, or ~25 mN thrust and ~1,400 s Isp on xenon. Following Astra’s acquisition, the product was rebranded as the Astra Spacecraft Engine (ASE) and offered in single- and multi-thruster configurations scaling to 1,600 W. Customers and flight heritage include York Space Systems (LEO constellation) and Spaceflight Inc.’s Sherpa-LTE orbital transfer vehicle; the thruster family has flown on multiple orbital missions and been ground-tested to over 12,000 operational cycles.
Documentation
Need the full ICD, test reports or a specific revision? Ask the supplier directly.