Mass Beam Propulsion

Gerald Nordley provided a mass beam propulsion overview at Space Access 2019.

There have been many kinds of mass beam propulsion. Use of mass beams, instead of light, allows great efficiency by adjusting the beam velocity so the redirected mass is left near zero velocity relative to the source. There is no intrinsic limit to the proper frame map velocity that can be achieved. To make a propulsion system, subsystems need to be developed to acquire propulsive energy, accelerate the mass into a collimated beam, insure that the mass reaches the spacecraft and redirect the mass. A number of approaches to these requirements have been proposed and are summarized here. Generally, no new scientific discoveries or breakthroughs are needed. These concepts are supported by ongoing progress in robotics, in nanometre scale technologies and in those technologies needed to use of space resources for the automated manufacture of space-based solar power facilities. For mass beams specifically, work in particle sizing, acceleration, delivery and momentum transfer is needed.

There was a previous Mass beam propulsion, an overview in 2015 by Gerald Nordley and Adam Crowl.

In 1993, Gerald had a presentation on beam propulsion.

In 2002, Jordan Kare published High-acceleration Microscale Laser Sails for Interstellar Propulsion. Laser pushed micro-sails are used to propel a large spacecraft by impacting a pusher plate.

There is a recent NIAC study on combined laser-particle beam propulsion. A combined beam might be able to limit beam spread.

SOURCES – Live coverage of presentation by Gerald Nordley at Space Access 2019, Background papers by Gerald Nordley and Jordin Kare.
Written By Brian Wang,

2 thoughts on “Mass Beam Propulsion”

  1. Lest we forget…

    There are charged ion beams and uncharged “neutral beams”. With the exception of beams of pellets, etc., neutral beams start out as ion beams, 50% electrons and 50% nuclei, which combine into “neutral” beams a few score meters past the exit port.  This recombination is charge-neutral and is much more strongly resistant to decollimation post-acceleration.  

    The really big problem is keeping a beam of atoms more-or-less going the same exact direction with esquisite precision and retaining the collimation (“focus”) so that the target (receding spaceship) has its collector/deflector plates intercepted.

    Yet, the neutral beam also presents the “opposite problem” at the receiver end.  

    Namely, no real efficient way to deflect the beam — harvesting the momentum — without ionizing it.  The ionization is particularly costly energetically. Oh, some schemes call for passing the neutral beam thru extraordinarly thin foils of electron-rich metals such as gold-on-beryllium, the idea being that neutral molecules or atoms passing thru dense electron-sea clouds will tend to have some of their electrons stripped.  The resulting positive ion beam can then be strongly deflected electrically off to the sides, harvesting the inertia.  

    I guess it works. I just know that when the sender isn’t spot-on with beam targeting accuracy, there is nothing at all that the receiver can do in the shortest of timespans to reacquire the neutral beam.

    Just saying,
    GoatGuy ✓


Leave a Comment