density of stars in space in RECONS.png [ 50.94 KiB | Viewed 609 times ]
Cyborg IM1 wrote:
So, for every F-type star you add, you should add 2 G-types, 3 K-types and about a dozen M-type stars.
Yeah, but closer in you add M-types without adding any Gs, and a little further out, Ks without Fs.
I had a bit of a look at the trend of the space density of stars in the RECONS set, and after allowing for a freakish spike between 11.27 and 11.83 light-years from Sol (there are six multiple systems all in that narrow range of distances from Sol: EZ Aquarii, 61 Cygni, Procyon, Gliese 725, GX & GQ Andromedae, and Epsilon Indi) it looks as though the trend is flat (and therefore no stars missing because of distance) at 0.0033 stars per cubic light-year. The volume covered by the RECONS set is 49,647 cubic light years, and contains 8 white dwarfs, 98 M-type stars, 18 K-type, 7 G-type, 1 F-type, and 2 A-type. You have to be careful about the small numbers because of sampling error, but the catalogues ought to be fairly complete for O, B, A, and perhaps F types anyway, at least as far as they are good for anything. That said, it basically looks as though you ought to add sufficient stars at each distance to maintain an average of about 0.00016 D-type, 0.00197 M-type, 0.000363 K-type, and 0.00014 G-type stars per cubic light-year.
I'm off to have a look at density trends by type in the HYG catalogue.