Realistic distance between stars?
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far-trader
SOC-14 10K
It depends 
On the density of the region. Offhand, for our near star cluster (those closest to and around Earth/Sol it's about 8 light years on average. The closest star to Sol is about half that though. But we are out in an arm of the galaxy. Densities in the core will be higher and there will be regions throughout that are above and below any average.
On the density of the region. Offhand, for our near star cluster (those closest to and around Earth/Sol it's about 8 light years on average. The closest star to Sol is about half that though. But we are out in an arm of the galaxy. Densities in the core will be higher and there will be regions throughout that are above and below any average.
Andrew Boulton
The Adminator
1 or 2 hexes
Actually, Traveller probably got it about right.
Actually, Traveller probably got it about right.
I recall reading (a book by Isaac Asimov, non-fiction, but I don´t recall the title) that the average distance between star in this galaxy, averaged out across all the galaxy, is about 7.5 light years.
This includes the galactic core, as well as the - more or less starless - space between the galactic arms. As a "quick and dirty" solution I´d say that the higher density at the core and the empty space between the arms more or less cancel each other out as deviation, and that the average distance between two stars in our galactic arm is about 7.5 light years. That´s about 2.3 parsecs/hexes in Traveller.
This includes the galactic core, as well as the - more or less starless - space between the galactic arms. As a "quick and dirty" solution I´d say that the higher density at the core and the empty space between the arms more or less cancel each other out as deviation, and that the average distance between two stars in our galactic arm is about 7.5 light years. That´s about 2.3 parsecs/hexes in Traveller.
daltoncalford
SOC-12
Well, based upon gliese 3.0 and other such databases, there are approx 77000 known stellar objects in the radius of 1000ly from earth (306.8 parsec radius - doing this from memory so I may be a little off).
The volume of that space is volume=4/3¶r3 or
120902646.95635622978601780028863 cubic parsecs
so divide that by the number of objects (and this does not really work out since some of those objects are in the same parsec as another)
and you find out that for every parsec with an object in it there are 1570+ cubic parsecs without anything in them....
As the gliese data shows that the stars seem to follow strands (think of lines of stars that keep them within a certain distance of another star) you start to see the idea of 'mains' such as the spinward main developing, combined with the idea of rifts. Now, 1000ly of earth is still all within our arm of the milkyway galaxy and does not go above or below the plane of the galaxy, nor does it intersect the voids between the arms of our galaxy.
There is alot of empty space out there...
just a point to ponder while I try to get a rectifier to come back online for our DC power plant.
best regards
Dalton
The volume of that space is volume=4/3¶r3 or
120902646.95635622978601780028863 cubic parsecs
so divide that by the number of objects (and this does not really work out since some of those objects are in the same parsec as another)
and you find out that for every parsec with an object in it there are 1570+ cubic parsecs without anything in them....
As the gliese data shows that the stars seem to follow strands (think of lines of stars that keep them within a certain distance of another star) you start to see the idea of 'mains' such as the spinward main developing, combined with the idea of rifts. Now, 1000ly of earth is still all within our arm of the milkyway galaxy and does not go above or below the plane of the galaxy, nor does it intersect the voids between the arms of our galaxy.
There is alot of empty space out there...
just a point to ponder while I try to get a rectifier to come back online for our DC power plant.
best regards
Dalton
The thing you have to remember using real astronomy catalogs is an artificial density drop-off based on visibility. There is a large drop in observable objects beyond near space. Dim trash stars like brown dwarfs exist in large numbers, but are hard to detect beyond a few parsecs.
A theoretical 'realistic' 2D star map would have at least one stellar object in a large majority of hexes.
A theoretical 'realistic' 2D star map would have at least one stellar object in a large majority of hexes.
The majority of stars are class M. The majority of visible stars are not -- while the brighter star classes are less common, they are visible at vastly greater distances. Of the 20 brightest stars (as seen from earth), 11 are giants or supergiants, off of the main sequence, and of the main sequence stars, there are 4xB, 3xA, 1xF, and 1xG. 9 of the 20 brightest stars have luminosities in excess of 1,000, and only two are below 10 (Alpha Centauri at 1.3, Procyon at 7.6)
IIRC (from the same book by Asimov), "useful stars" - in the sense that they could have planets supporting live - are all main sequence stars, I think categories F, G and K and maybe the hotter M and cooler A stars, that are either single stars, or in a multiple system with their other "useful stars" or red dwarves (i.e. category M). A giant or supergiant companion would explode before complex life can possible develop, thus sterilizing the planets.
As it happens, the nearest (to Sol) star system that meets these criteria is Alpha Centauri, at 1.33 parsec (4.4 light years) distance, with a F and a G main sequence star and a category M red dwarf.
Anyway, according to Asimov, about 1 in 4 stars in the galaxy could be considered "useful stars"
As it happens, the nearest (to Sol) star system that meets these criteria is Alpha Centauri, at 1.33 parsec (4.4 light years) distance, with a F and a G main sequence star and a category M red dwarf.
Anyway, according to Asimov, about 1 in 4 stars in the galaxy could be considered "useful stars"
