It's... not full of stars!

Reynard

Emperor Mongoose
I was having a bit of fun letting the Heaven & Earth program create a sector using the standard 50% occurance. The sector was very crowded with stars of course.

Years ago, I plotted all stars local to Sol for about twenty lightyears for use as a realistic Traveller setting and saw jump drives would be less useful consitering distances. Combining the two ideas, I wondered what a true 'standard' density would be. Found information showing there are 1049 non-brown dwarf stars (those are very hard to find) withing a radius of 65 lys from Sol or 1 star per 1000 cubic parsecs or 29 cubic parsecs. That's about 3.5% occurance per unit, way below 50%! The older Traveller system had Rift density at about 3% or rolling a 12 on two dice.

If my math is right, that same spherical volume around Sol would contain about 17,483 stars!
 
Reynard said:
I was having a bit of fun letting the Heaven & Earth program create a sector using the standard 50% occurance. The sector was very crowded with stars of course.

Years ago, I plotted all stars local to Sol for about twenty lightyears for use as a realistic Traveller setting and saw jump drives would be less useful consitering distances. Combining the two ideas, I wondered what a true 'standard' density would be. Found information showing there are 1049 non-brown dwarf stars (those are very hard to find) withing a radius of 65 lys from Sol or 1 star per 1000 cubic parsecs or 29 cubic parsecs. That's about 3.5% occurance per unit, way below 50%! The older Traveller system had Rift density at about 3% or rolling a 12 on two dice.

If my math is right, that same spherical volume around Sol would contain about 17,483 stars!

You would need to plot their relative distances and do up a 3D map parsec to determine whether it creates a problem for using J-Drives... The raw data you present doesn't really address that.
 
Actually I created a spreadsheet showing every distance between all stars then calculated jump numbers. Even Sol to Alpha Cent and Proxima were short for Jump 1. More routes at Jump 2 and 3. I even hand drew a map with various Jump routes. All in all, the real local star systems are not Traveller friendy at low tech levels.

I'm still trying to picture a sky with seventeen times as many near stars several as close as Alpha cent.
 
Can you show us your result? I'd be very interested to see an accurate depiction of Sol and near stars in a Traveller style map &/or spreadsheet.
 
I suspect the closest you can get to a map of the near stars
would look more like this than anything resembling a Travel-
ler map:

http://upload.wikimedia.org/wikipedia/commons/f/ff/Nearby_Stars_%2814ly_Radius%29.svg
 
rust said:
I suspect the closest you can get to a map of the near stars
would look more like this than anything resembling a Travel-
ler map:

http://upload.wikimedia.org/wikipedia/commons/f/ff/Nearby_Stars_%2814ly_Radius%29.svg

That's how SPI's Universe went about it.
 
Reynard, F33D, I understand how true standard density is being computed but why is this a problem for J-Drive? Gravity objects (stars) in the way? Too many in straightline paths? Got lost, trying to understand.
 
This was just an exercise in comparing game mechanics to reality for me not an attempt to show Traveller is all wrong or something silly like that. The problem is stars in our reality are much farther apart than we see in standard Traveller maps. Earth would be waiting a long time before exploring the stars since even Proxima is slightly beyond Jump 1. I partially solved this problem by making a Jump unit to the far edge of the hex rather than the center so a Jump is a hex and a half or, for a 3D representaion, about 5 lightyears instead of 3.3 lightyears.

Rust you're right. 10-15 years ago when I did my map I had a hard time finding such maps on the net. I still have the map and a hardcopy of the spreadsheet which was lost in the Computer Crash of '05. I created my map to see jumps related to the various systems. It let me see how these routes would influence colonization. I'd love to show the map but don't know where to put it except maybe facebook.

Mr31337, my map is 3D rather than 2D hex. You really can't represent it on a hex map though there have been old publications showing a much simpler set of near Sol stars on a hex grid with nowhere near as many local stars. My original influence was actually the map and list of star corrdinates from the 1988 2300AD boxed set with the formula to calculate distances between any two stars.
 
Nathan Brazil said:
Reynard, F33D, I understand how true standard density is being computed but why is this a problem for J-Drive? Gravity objects (stars) in the way? Too many in straightline paths? Got lost, trying to understand.


Naw. We're talking about the jump distance between star systems near us.

BTW - here are some 3D maps of our neighborhood.
http://www.closeststars.com/Home_Page.html

And here is some detail about nearby stars & density of our immediate area.
http://www.astro.wisc.edu/~dolan/constellations/extra/nearest.html
 
Well that is the inherent problem of relying on a hexmap to accurately layout a universe. Fuzzy logic is some what needed. Btw can you use a jumpdrive in space out side a solar system to just do two jumps, one full jump followed by a short jump. A sector with a realistic map could have a society that utalises either external fueltanks. An almost secondary fuelmodule for interstellar travel with a two part ship system one a streamlined module for planatary operations with the secondary unit that contains the extra fuel to facilitate extra jumps. These modules could be connected and disconnected at a on needs basis. Almost like the Nostromo from the movie Alien.
 
Another possibility would be deep space fuel depots to link essential space routes and important worlds where going around would be very expensive and/or time comsuming.

In Traveller, we're used to systems commonly grouped into mains with plenty of gas giants and even water for fuel. I believe the original Traveller game didn't make fuel scoops and purifiers a regular or cheap addition so starport refueling rather than gas skimming was the norm. Viewing sectors or subsectors to see the patterns of trade and world importance, would gaps between systems or clusters of system see more depots? These would be huge stations catering to ship traffic needing a bounce to the next system especially all those Jump 1 and 2 traders and liners. Tankers would deliver harvested fuels from the nearby system a jump or two away and those giants may even be consitered property of the depot not to be skimmed for free. The depots may also be business hubs where goods are bought and sold from either side of the gap. Hotels and attractions could be common for stopovers to sttretch your legs before getting back into a cramped ship for another week. Well placed depots can be a place of adventure as any planet.
 
Reynard said:
Another possibility would be deep space fuel depots to link essential space routes and important worlds where going around would be very expensive and/or time comsuming.

In Traveller, we're used to systems commonly grouped into mains with plenty of gas giants and even water for fuel. I believe the original Traveller game didn't make fuel scoops and purifiers a regular or cheap addition so starport refueling rather than gas skimming was the norm. Viewing sectors or subsectors to see the patterns of trade and world importance, would gaps between systems or clusters of system see more depots?

Given what we now know, it would probably be bridged by using cool brown dwarfs as refueling points.
 
Reynard said:
Actually I created a spreadsheet showing every distance between all stars then calculated jump numbers. Even Sol to Alpha Cent and Proxima were short for Jump 1. More routes at Jump 2 and 3. I even hand drew a map with various Jump routes. All in all, the real local star systems are not Traveller friendy at low tech levels.
This is why old (Jump-1) ships in my Outer Veil setting use empty-hex jumps and always carry double fuel. Getting from Sol to Alpha Centauri takes two weeks, including a calibration in real-space. Ships carry supply for much longer than in the OTU and are built for yearly rather than monthly maintenance. New Jump-2 ships can get from Sol to Alpha Centauri in a single week - but are expensive cutting-edge tech.

Note that for the sake of convenience and compatibility with other Traveller products, Outer Veil uses a 2D hex-map, which was "flattened" from real (2008 IIRC) star data and guesstimated into the hex grid; some red and brown dwarfs were also added to the map (as they are probably more numerous than what we can see from Earth).
 
"Given what we now know, it would probably be bridged by using cool brown dwarfs as refueling points."

They don't give great descriptions on the working of stellar/planetary sensors but Scouts does mention gas giants are part of initial detection. If you add brown dwarves, essentially very big gas giants, I could see surveys detecting them at stellar distances with at least TL 9+ equipment. The only problem could be they might not be in the 'empty' space convenient for jump routes. On the other hand, if you have a more realistic depiction of space, there will be far fewer useful star systems but a lot of failed stars filling in meaning spending many weeks dwarf hopping to reach your real goal.
 
Reynard said:
"Given what we now know, it would probably be bridged by using cool brown dwarfs as refueling points."

They don't give great descriptions on the working of stellar/planetary sensors but Scouts does mention gas giants are part of initial detection. If you add brown dwarves, essentially very big gas giants, I could see surveys detecting them at stellar distances with at least TL 9+ equipment. The only problem could be they might not be in the 'empty' space convenient for jump routes. On the other hand, if you have a more realistic depiction of space, there will be far fewer useful star systems but a lot of failed stars filling in meaning spending many weeks dwarf hopping to reach your real goal.


We can detect them light years away with crappy TL 7 sensors. They are thought to make up, on the low side, about 25% of all stars. Roll for each "empty hex". Also, we have NO real idea as to what an average star system is like as far as useful planets. It may be MORE than Trav depicts...
 
Reynard said:
"Given what we now know, it would probably be bridged by using cool brown dwarfs as refueling points."

They don't give great descriptions on the working of stellar/planetary sensors but Scouts does mention gas giants are part of initial detection. If you add brown dwarves, essentially very big gas giants, I could see surveys detecting them at stellar distances with at least TL 9+ equipment. The only problem could be they might not be in the 'empty' space convenient for jump routes. On the other hand, if you have a more realistic depiction of space, there will be far fewer useful star systems but a lot of failed stars filling in meaning spending many weeks dwarf hopping to reach your real goal.

Brown Dwarfs are more than just "very big gas giants" (actually, they're about the same size as Jupiter, just 13-80 times more massive) - they're also emitting a lot more heat than a gas giant would, which means they're more detectable on IR sensors. Still, we have a hard time detecting them beyond about 6 pc with current telescope/surveying technology.

That said, chances are that they *are* in the convenient empty spaces between stars - there is likely to be a lot of them out there - possibly even more than the number of stars!
 
Wil Mireu said:
Brown Dwarfs are more than just "very big gas giants" (actually, they're about the same size as Jupiter, just 13-80 times more massive) - they're also emitting a lot more heat than a gas giant would, which means they're more detectable on IR sensors. Still, we have a hard time detecting them beyond about 6 pc with current telescope/surveying technology.

That said, chances are that they *are* in the convenient empty spaces between stars - there is likely to be a lot of them out there - possibly even more than the number of stars!

Do you happen to know what the latest estimate is as to % of stars being Browns?
 
One source I saw says we know about 1800 of them. One pair is 6.5 lys away and another pair is 12 lys. I didn't see any mention how far away most are.
 
F33D said:
Do you happen to know what the latest estimate is as to % of stars being Browns?

Zero? ;) (brown dwarfs are not stars :P )

Though seriously, what I originally said appears to be out of date: WISE didn't find as many BDs - at least in the solar neighbourhood - as had previously been assumed to exist. It looks like there's about 1 BD for every 6 stars near Sol, unless WISE is missing some really cold (less than room temperature) objects.

See: http://www.space.com/16112-brown-dwarf-stars-sun-rare.html

It could vary with location though - in or near young star clusters there may be way more BDs than can be found around here.
 
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