﻿COUNTIISrG 
  THE 
  STARS 
  SEAEES 
  199 
  

  

  when 
  we 
  count 
  to 
  a 
  very 
  faint 
  limit, 
  we 
  include 
  such 
  enormous 
  numbers 
  

   of 
  stars 
  belonging 
  to 
  the 
  larger 
  system 
  that 
  the 
  local 
  system 
  has 
  no 
  

   appreciable 
  influence 
  on 
  the 
  observed 
  distribution; 
  the 
  stars 
  crowd 
  

   toward 
  the 
  great 
  fundamental 
  plane 
  of 
  the 
  Milky 
  Way, 
  and 
  the 
  center 
  

   appears 
  in 
  its 
  true 
  direction 
  toward 
  Sagittarius, 
  in 
  longitude 
  325°. 
  

  

  Finally, 
  if 
  we 
  suppose 
  the 
  local 
  system 
  to 
  be 
  a 
  little 
  to 
  the 
  south 
  of 
  

   the 
  plane 
  through 
  the 
  Milky 
  Way 
  clouds, 
  and 
  the 
  sun 
  almost 
  exactly 
  

   in 
  this 
  plane, 
  we 
  account 
  for 
  the 
  relative 
  numbers 
  of 
  stars 
  on 
  opposite 
  

   sides 
  of 
  the 
  Milky 
  Way 
  — 
  an 
  excess 
  of 
  bright 
  stars 
  to 
  the 
  south, 
  and 
  an 
  

   equal 
  division 
  of 
  faint 
  stars 
  between 
  the 
  two 
  halves 
  of 
  the 
  sky. 
  

  

  The 
  star 
  counts 
  even 
  tell 
  us 
  something 
  about 
  the 
  size 
  of 
  the 
  local 
  

   system, 
  for 
  both 
  Figure 
  2 
  and 
  the 
  relative 
  numbers 
  of 
  stars 
  north 
  and 
  

   south 
  of 
  the 
  Milky 
  Way 
  (p. 
  197) 
  show 
  that 
  the 
  influence 
  of 
  this 
  sj^stem 
  

   can 
  be 
  traced 
  down 
  to 
  about 
  the 
  sixteenth 
  magnitude. 
  From 
  this 
  

   circumstance 
  alone 
  it 
  seems 
  likely 
  that 
  we 
  should 
  still 
  find 
  stars 
  be- 
  

   longing 
  to 
  the 
  local 
  system 
  at 
  a 
  distance 
  of 
  10,000 
  light 
  years 
  from 
  the 
  

   sun. 
  Other 
  features 
  of 
  Figure 
  2, 
  supplemented 
  by 
  other 
  information, 
  

   indicate 
  that 
  the 
  members 
  of 
  the 
  local 
  system 
  are 
  to 
  be 
  counted 
  by 
  

   many 
  millions, 
  and 
  that 
  they 
  comprise 
  something 
  like 
  three-fourths 
  

   of 
  all 
  the 
  stars 
  in 
  our 
  immediate 
  neighborhood 
  in 
  space; 
  the 
  larger 
  

   system 
  would 
  thus 
  contribute 
  only 
  a 
  fourth 
  of 
  the 
  total 
  stellar 
  popula- 
  

   tion 
  near 
  the 
  sun. 
  

  

  The 
  dominating 
  influence 
  of 
  the 
  local 
  system 
  may 
  be 
  shown 
  very 
  

   simply 
  by 
  examining 
  star 
  counts 
  in 
  another 
  way. 
  In 
  studying 
  the 
  

   numbers 
  of 
  stars 
  added 
  by 
  extending 
  the 
  counts 
  downward, 
  magnitude 
  

   after 
  magnitude, 
  the 
  results 
  in 
  different 
  longitudes, 
  as 
  already 
  ex- 
  

   plained, 
  were 
  averaged. 
  To 
  gain 
  a 
  general 
  idea 
  of 
  how 
  stars 
  are 
  

   scattered 
  throughout 
  space, 
  we 
  ignored 
  the 
  fact 
  that 
  we 
  might 
  not 
  be 
  

   at 
  the 
  center 
  of 
  the 
  s^^stem, 
  and 
  were 
  led 
  by 
  the 
  ratios 
  in 
  Table 
  II 
  to 
  

   conclusions 
  which 
  likened 
  the 
  stellar 
  system 
  to 
  a 
  much-flattened 
  swarm 
  

   of 
  bees, 
  thinning 
  out 
  in 
  numbers 
  from 
  the 
  center 
  toward 
  the 
  edge. 
  

   Now, 
  however, 
  we 
  loiow 
  that 
  we 
  are 
  far 
  from 
  the 
  center 
  of 
  the 
  swarm 
  ; 
  

   and 
  it 
  seems 
  likely 
  that 
  were 
  we 
  to 
  proceed 
  in 
  the 
  direction 
  of 
  that 
  

   point, 
  we 
  might 
  find 
  the 
  stars 
  crowding 
  together, 
  while 
  in 
  the 
  opposite 
  

   direction 
  we 
  should 
  find 
  them 
  thinning 
  out 
  even 
  more 
  rapidly 
  than 
  

   the 
  average 
  counts 
  indicate. 
  This 
  at 
  least 
  would 
  be 
  the 
  expectation 
  

   were 
  it 
  not 
  for 
  the 
  presence 
  of 
  the 
  local 
  system. 
  

  

  When 
  we 
  turn 
  again 
  to 
  the 
  original 
  counts 
  to 
  see 
  how 
  those 
  in 
  

   different 
  directions 
  along 
  the 
  Milky 
  Way 
  increase 
  in 
  numbers 
  as 
  we 
  

   add 
  fainter 
  and 
  fainter 
  stars, 
  we 
  find 
  that 
  they 
  build 
  up 
  much 
  faster 
  

   in 
  the 
  direction 
  of 
  the 
  center 
  than 
  toward 
  the 
  opposite 
  point 
  in 
  the 
  

   sky, 
  but 
  not 
  nearly 
  fast 
  enough 
  to 
  indicate 
  any 
  crowding 
  of 
  stars 
  as 
  

   the 
  center 
  is 
  approached. 
  On 
  the 
  contrary, 
  the 
  ratios 
  are 
  such 
  that, 
  

   as 
  we 
  leave 
  our 
  neighborhood 
  in 
  space, 
  the 
  stars 
  must 
  begin 
  to 
  thin 
  

   out 
  almost 
  at 
  once, 
  whatever 
  the 
  direction 
  in 
  which 
  we 
  proceed 
  out- 
  

  

  