Some thoughts on the scaling between planetary systems and the galaxy

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Osito
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Some thoughts on the scaling between planetary systems and the galaxy

Post by Osito »

[Edited the title, as it was too long: should have spent more time thinking about the scaling of my title length!]

I've been looking into the relative size of the DW planetary systems compared with the scale of the galaxy (i.e. the distances between the stars), and have some information which is probably already totally obvious to anyone else who has ever thought about it. I'm gonna share it anyway, because I'm interested in the views of others and it does affect the way you might try to create a galaxy with consistent dimensions. It also affects any 'real world' values you might try to assign to distance and speed in DW. This in turn has an effect on anyone who is trying to mod the speeds of the hyperdrives to fit in with a galaxy of specific dimensions.

As many of you will know, in the editor there is a maximum distance from the star at which you can place planets, which I will call the 'system diameter'. This is about 45,000 in-game 'distance units'. (Just to recap each sector is a square with sides equivalent to about 2 million distance units. So the maximum planetary radius of a solar system is about 2.25% of the sector length.)

In DW, 300 seconds (real time) is equivalent to 6 months in-game time (180 days), i.e., 1 day = 1.6 seconds.

A hyperdrive with speed 28125 would cross the maximum system diameter (45000) in 1.6 seconds, i.e., in 1 day of game time. To compare that with a real world example: in our own solar system, light would cross the diameter of Pluto's orbit in about half a day.

The warp bubble generator is the first hyperdrive. Properly powered it will travel at a speed of 2000, so it's reasonable to assume that speed 2000 is the maximum possible value for the speed of light in unmodded DW (because if the speed of light were, say, 2100, then the warp bubble generator would be a sub-light drive). However, a warp bubble generator would take about 22.5 seconds to cross the system diameter, i.e., about 2 weeks' game time. That is a very big system (compare with Pluto, as described above: if you were building our solar system in a DW scale, you would need to place Pluto so close to the sun that there would be barely any room to place any other planets).

If speed 2000 is the speed of light, then the total size of a 15x15 sector galaxy would be around 25 light years by 25 light years. If you assign a lower speed value as being equivalent to the speed of light, you can increase the dimensions of the galaxy, but you also massively increase the size of the system diameter.

Conversely, if you set the speed of light to a higher value than 2000 you can reduce the system diameter, but you also reduce the size of the rest of the galaxy. For example, if you set the speed of light at an in-game speed of about 56000, then the system diameter would be approximately in line with the size of Pluto's orbit, but the size of the galaxy would be less than one light year across.

This all leads me to the conclusion that consistent scaling between the system and stellar levels is not really practical. This is not a surprise, nor is it a big deal. As observed elsewhere, you cannot properly scale the relative sizes of the stars and planets in DW, nor can you properly scale the distances of the planets from the sun in our own solar system - to try to do so would be completely impractical. However, in my opinion it does have the consequence that you cannot in any practical sense assign a value to the speed of light in terms of ship speed.

Edit: in practice, I think the best way to approach this, if you're trying to mod the galaxy and the ship speeds to represent 'real world' values, is to concentrate on the galactic scale, and get the distance and speeds right there, then pretty much ignore the effect that has on the system scale.

Well, what else was I supposed to do while I wait for DW:U to get released?
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Bingeling
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RE: Some thoughts on the scaling between planetary systems and the galaxy

Post by Bingeling »

Without calculating anything...

How large is a spaceship compared to the earth? It is a dot on the picture, it is insignificant.
If we look at the solar system? How large is the earth? It is a dot in the vast area of empty space. As are any other planet, even if we choose a weird 2D representation of the solar system in the plane of the planets.

How large is the solar system compared to a stretch covering the 20 nearest neighbors in the galaxy? A dot on the map.

Trying to make it match the real world is pointless. For fun it can be nice if something is consistent around the game concepts.

The galaxy consists of mostly empty space. This should be somewhat true at least until they actually discover anti matter... Empty space is not fun :)

A galaxy in this game is one where carbon fibre is a rare thing in a galaxy full of organic life. A rather artificial one ;)
Raap
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RE: Some thoughts on the scaling between planetary systems and the galaxy

Post by Raap »

To make a real-scaled universe I think you'd pretty much have to have 3D and a camera that was object-focused rather than free-form top-down. That fits much better with 'space is 99.9999% empty', since you won't be forced to spend most of your time scrolling and zooming, but rather jump between actual objects.

At any rate, I don't consider it particularly important. What I would like is slower pace/bigger scale overall. Especially in terms of hyperspeed, but maybe also in-system speed. I just fear that the AI wouldn't particularly enjoy such changes.
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Darkspire
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RE: Some thoughts on the scaling between planetary systems and the galaxy

Post by Darkspire »

This might help ...

Star Size Comparison HD

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Tavior
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RE: Some thoughts on the scaling between planetary systems and the galaxy

Post by Tavior »

Personally I like this one far better.

You can zoom pretty far in-close and far away.

http://scaleofuniverse.com/
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Darkspire
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RE: Some thoughts on the scaling between planetary systems and the galaxy

Post by Darkspire »

ORIGINAL: Tavior

Personally I like this one far better.

You can zoom pretty far in-close and far away.

http://scaleofuniverse.com/

Sense of scale is there but it kind of gets a bit lost.

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Osito
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RE: Some thoughts on the scaling between planetary systems and the galaxy

Post by Osito »

They're ok, but I'm using Starry Night Pro Plus, myself. Now that really gives a sense of the scale.
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feygan
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RE: Some thoughts on the scaling between planetary systems and the galaxy

Post by feygan »

I think the overall best way is to try an separate star systems and galactic space from each other. The mechanics of the game just do not allow you to realistically combine them without huge compromises to the validity of both. However it is safe to guess that the engines ships use for sub light travel are only capable of a fraction of that speed. There have been numerous sci-fi shows that tackled this sort of thing with technobable and throwing in the issue of time dilation at that sort of speed.

Thus for me ship thruster engines are something that is primarily used for maneuvers either in combat or docking etc. Otherwise they can simply give you lots of thrust over long distance (between planets) but require complex math to make it a point to point thing. Similar to how we now send craft to Mars etc.

The invention of a form of ftl travel would wipe out conventional travel almost overnight, this has been shown numerous times through history in that almost no one walks or rides a horse for transport other than pleasure when they have an internal combustion engine that does it faster. This again helps lend credence to why thrust engines are used only for close range maneuvers.

With that in mind it is the reality of the galatic scale that matters, far better to make a journey 100 light years last months or even years than to have to wave away the fact the galaxy is actually only 20 light years across. Or worse that a species can cross that 100 light years in a week or less but doesn't have the technological ability to govern more than a few planets without help beyond a certain range (they can travel that far physically but the messages get lost in the post?).
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DeadlyShoe
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RE: Some thoughts on the scaling between planetary systems and the galaxy

Post by DeadlyShoe »

IMO, it's fairly easy to handwave this as solar systems being 'brown water' where you can only go so fast safely. Interstellar space is blue water where you go as fast as you want.
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