3 ms·

That looks awesome! The photo of the plasma discharge from the solid molybdenum fuel rod in the datasheet is worth looking at [1], perfectly illustrating the "C

That looks awesome! The photo of the plasma discharge from the solid molybdenum fuel rod in the datasheet is worth looking at [1], perfectly illustrating the "Centre-Triggered Pulsed Cathodic Arc" that is the basis for this thruster. The ion and hall effect thrusters that this drive would replace require a propellant tank to hold xenon, krypton, iodine, etc. so integrating them is a bit of a pain in the ass. Anyone know how the mass stacks up though? Hall effect thrusters from Busek have a (much) higher power/mass ratio but that doesn't include the propellant tank. [1] https://neumannspace.com/wp-content/uploads/2023/09/Neumann-Drive-Datasheet_Sept-2023.pdf https://neumannspace.com/wp-content/uploads/2023/09/Neumann-...

xoa 3y ago
>Anyone know how the mass stacks up though? I haven't been able to find that yet, but even if significantly worse this may still have an important big upcoming space. In the upcoming Starship era, economics is going to play a historically huge new role in space, just as it does in Starship itself where many of the design and material decisions are optimized around cost and simplicity, even at some performance penalty, vs the old space total focus on perf. A drive that performs worse, but is much easier and cheap, could be useful alongside the others in some roles when you can throw 100+ tons at a problem at <$200/kg to LEO, or even <$100/kg.
axus 3y ago
Good data sheet! I wonder where it fits on this table: https://en.wikipedia.org/wiki/Spacecraft_propulsion#Table_of_methods https://en.wikipedia.org/wiki/Spacecraft_propulsion#Table_of... Also looked at this table: https://en.wikipedia.org/wiki/Ion_thruster#Comparisons https://en.wikipedia.org/wiki/Ion_thruster#Comparisons The weight on this one looks really good, not even counting the lack of propellant. I'm going to guess that has a downside, that the total impulse is limited by how small the fuel rod is.
- mikewarot 3y ago
  >the lack of propellant The molybdenum rod IS the propellant. It eventually ends up out in space. I'm only aware of one propellantless thruster, and I'm waiting to see if it works aboard Barry-1[1] It uses electric power in an entirely closed drive, generating 1 milli-newton of thrust. It should be switched on in a month or two. [1] https://celestrak.org/NORAD/elements/graph-orbit-data.php?CATNR=58338 https://celestrak.org/NORAD/elements/graph-orbit-data.php?CA...
  - throwawaymaths 3y ago
    Do you have citation on that it's gonna be switched on in a month? Have been curious about this
  - boznz 3y ago
    I am aware of zero propellant less drives. My Prescence on the internet and news sites is not what it used to be but I'm sure I wouldn't have missed Newtons laws being upended.
dmichulke 3y ago
> That looks awesome! "Power overwhelming" comes to mind

xoa 3y ago

>Anyone know how the mass stacks up though? I haven't been able to find that yet, but even if significantly worse this may still have an important big upcoming space. In the upcoming Starship era, economics is going to play a historically huge new role in space, just as it does in Starship itself where many of the design and material decisions are optimized around cost and simplicity, even at some performance penalty, vs the old space total focus on perf. A drive that performs worse, but is much easier and cheap, could be useful alongside the others in some roles when you can throw 100+ tons at a problem at <$200/kg to LEO, or even <$100/kg.

axus 3y ago

Good data sheet! I wonder where it fits on this table: https://en.wikipedia.org/wiki/Spacecraft_propulsion#Table_of_methods https://en.wikipedia.org/wiki/Spacecraft_propulsion#Table_of... Also looked at this table: https://en.wikipedia.org/wiki/Ion_thruster#Comparisons https://en.wikipedia.org/wiki/Ion_thruster#Comparisons The weight on this one looks really good, not even counting the lack of propellant. I'm going to guess that has a downside, that the total impulse is limited by how small the fuel rod is.

mikewarot 3y ago
>the lack of propellant The molybdenum rod IS the propellant. It eventually ends up out in space. I'm only aware of one propellantless thruster, and I'm waiting to see if it works aboard Barry-1[1] It uses electric power in an entirely closed drive, generating 1 milli-newton of thrust. It should be switched on in a month or two. [1] https://celestrak.org/NORAD/elements/graph-orbit-data.php?CATNR=58338 https://celestrak.org/NORAD/elements/graph-orbit-data.php?CA...
- throwawaymaths 3y ago
  Do you have citation on that it's gonna be switched on in a month? Have been curious about this
- boznz 3y ago
  I am aware of zero propellant less drives. My Prescence on the internet and news sites is not what it used to be but I'm sure I wouldn't have missed Newtons laws being upended.

dmichulke 3y ago

> That looks awesome! "Power overwhelming" comes to mind