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-   -   [Spaceships] Magsail acceleration question (https://forums.sjgames.com/showthread.php?t=79712)

acrosome 05-12-2011 01:36 PM

[Spaceships] Magsail acceleration question
 
Does the acceleration of a magsail vary by the distance from a star according to the inverse square law, as does a lightsail? Logically it seems that it should, but the RAW in Spaceships doesn't seem to imply that.

If it doesn't, why not?

Anthony 05-12-2011 01:45 PM

Re: [Spaceships] Magsail acceleration question
 
Because the sail effect becomes larger or smaller depending on the solar wind, actual scaling is slower than inverse square.

acrosome 05-12-2011 10:57 PM

Re: [Spaceships] Magsail acceleration question
 
How does it scale, then?

Why not have the sail at maximum size all the time?

Langy 05-12-2011 11:17 PM

Re: [Spaceships] Magsail acceleration question
 
Quote:

Originally Posted by acrosome (Post 1174773)
How does it scale, then?

Why not have the sail at maximum size all the time?

The scale is close enough to 'doesn't scale at all' that it doesn't matter, given the granularity of Spaceships.

The sail's size depends upon various conditions, but the long and short of it is that the sail is always at maximum size - the maximum size simply changes as you get closer (it contracts) or further away (it expands) from the star.

lexington 05-12-2011 11:25 PM

Re: [Spaceships] Magsail acceleration question
 
That's... weird. I'm can't seem to find any mention of that.

Sunrunners_Fire 05-12-2011 11:30 PM

Re: [Spaceships] Magsail acceleration question
 
Quote:

Originally Posted by lexington (Post 1174794)
That's... weird. I'm can't seem to find any mention of that.

Because it is a property of what a magsail is and gets way more detailed than spaceships is setup to handle. See here for a more in-depth explanation. Or the pdf here or here.

lexington 05-12-2011 11:55 PM

Re: [Spaceships] Magsail acceleration question
 
Quote:

Originally Posted by Sunrunners_Fire (Post 1174799)
Because it is a property of what a magsail is and gets way more detailed than spaceships is setup to handle. See here for a more in-depth explanation. Or the pdf here or here.

Those references don't say it grows and shrinks without deliberate action.

Sunrunners_Fire 05-12-2011 11:57 PM

Re: [Spaceships] Magsail acceleration question
 
Quote:

Originally Posted by lexington (Post 1174805)
Those references don't say it grows and shrinks without deliberate action.

Neither did Langy. Or are you assuming that a magsail doesn't have a dedicated automated system that makes adjustments as necessary and appropriate?

Langy 05-13-2011 12:20 AM

Re: [Spaceships] Magsail acceleration question
 
Quote:

Originally Posted by lexington (Post 1174805)
Those references don't say it grows and shrinks without deliberate action.

A mini-magnetospheric plasma propulsion system (which is a specific type of magsail) does have the sail automatically grow or shrink without deliberate action, I believe. The previously-linked references are primarily about a classic magsail, which uses physical wires to create the sail. The plasma system uses a plasma to carry the current instead, and automatically expands as the pressure drops.

I can't find the references to the plasma magsail I saw previously at the moment, though, so I can't say for sure how it all works.

EDIT: Though wikipedia agrees that it is automatic.

malloyd 05-13-2011 09:26 AM

Re: [Spaceships] Magsail acceleration question
 
The "sail" isn't physical, not even in the classic design. It's a volume around the current carrier limited by how far the magnetic field can reach. As the density of the particle wind goes down, the field can reach further away from the physical loop. It is after all the point to induce motion in those charged particles, and moving them sets up counterfields. The denser they are, the closer to your spaceship those induced fields will screen the rest of the universe from the field of your magsail.


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