
Ultrahigh Acceleration Neutral Particle Beam-Driven Sails - elorant
https://www.centauri-dreams.org/2019/01/03/ultrahigh-acceleration-neutral-particle-beam-driven-sails/
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awestroke
A 260-meter diameter magnetic sail weighing only 1kg would be quite fantastic
to see. I wonder if something based on carbon tubes could withstand 100,000g.
Acceleration at such levels would turn conventional metals liquid immediately.

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ncmncm
Dumb question: how do you couple to a beam of neutral particles?

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avian
From the article:

> The rapidly moving magnetic field of the Magsail, seen in the frame of the
> beam as an electric field, ionizes the incoming neutral beam particles.
> Nordley and Crowl discuss on-board lasers to ionize the incoming beam,
> although this adds additional on-board mass and power

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ohiovr
I like this idea. I was wondering if it would be possible to collect and focus
solar wind close to the sun and use it as a high concentration beam.

Was also wondering if you could use the various gyroradii and charge of solar
wind particles to “sort” them.

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sandworm101
No. Any structure that could do that would itself be pushed by the wind. The
energy/fuel needed for station keeping the focus unit would be better spent on
the actual spacecraft ... unless you want some megastructure (ring) that
wouldnt need fuel for station keeping.

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samsari
Shouldn't there be some sort of "lagrange-like" point where the sun's
gravitational pull balances out the push of the solar wind?

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stult
No, or at least not any stable such point, because the solar wind is not
constant. Plus it is orders of magnitude less powerful than the sun's gravity.
It's only usable (in theory) for navigation because any ship is already in
orbit around the sun and doesn't need to "cancel out" gravity in the sense
that wings provide lift to an airplane or a rocket achieves orbit from the
ground, but rather it needs to be able to gently and continuously nudge itself
into higher or lower orbits.

