The newest arrival to the space collection... a modern marvel from the SpaceX Starlink satellites used for on-orbit maneuvering. SpaceX has mastered Argon Hall Effect thrusters, something no one else has been able to do. This affords a 20x power density (4.2kW in 2.1kg) and much lower cost gas (about $10 per satellite) than prior designs using Krypton or Xenon. This is one of the early 2023 flight units for Starlink V2 Mini, and the only one outside the company.
Elon
commented on X: "The Starlink ion thruster is a marvel of engineering."
These thrusters are for in-space use only, and while they have relatively low thrust, they can run continuously for long periods with a very high ISP, and they are compact and reliable. They are commonly used for satellite station keeping and interplanetary missions, where this Argon thruster could reduce a 5-year transit time to months to reach Jupiter.
The backside of the SpaceX thruster shows how simple it is, with gas lines and wires for the cathode and electrode, insulated with Boron Nitride on the other side and permanent magnets for lensing of the streams. (see below for more images)
Ben Longmier, lead designer of the SpaceX thruster, gave it to me.
And more history from Ben: “One of the original Peenemunde rocket scientists on Von Braun’s team was Ernst Stuhlinger, who moved his family to what would become Marshall Spaceflight Center in Alabama. Ernst was close to Von Braun and worked on a lot of the early projects. In the later years of the US space program, both Ernst and Von Braun had dreams of expanding beyond the moon and sending craft deeper into the solar system, specifically Mars. One of Ernst’s concepts involved solar powered craft that would use Cesium ion thrusters to achieve a very high payload fraction delivered from Earth C3 to Mars injection orbit. This was an early solar electric propulsion concept that would ultimately never fly due to the wind down of budgets.”
And now, with the modern revival of a Mars program, the SpaceX Marslink satellites take us from dream to dream.
I borrow this phrase form the closing of Andrew Chaiken’s A Man on the Moon: “Historians of the far future may look back on Apollo and the missions that are yet to come as one great Age of Space Exploration. But in my mind’s eye it is a slow dissolve, from memory to anticipation, from what has been to what will be, from dream to dream.”
