﻿192 
  ANNUAL 
  REPORT 
  SMITHSONIAN 
  INSTITUTION, 
  19 
  2 
  9 
  

  

  III 
  

  

  ECCENTRIC 
  LOCATION 
  OF 
  THE 
  SUN— 
  DIRECTION 
  OF 
  THE 
  CENTER 
  

  

  The 
  symmetry 
  found 
  in 
  the 
  distribution 
  of 
  stars 
  on 
  opposite 
  sides 
  

   of 
  the 
  Milky 
  Way 
  shows 
  that 
  the 
  sun 
  and 
  its 
  planets 
  must 
  be 
  close 
  

   to 
  the 
  plane 
  passing 
  through 
  the 
  Milky 
  Way 
  and 
  the 
  center 
  of 
  the 
  

   system; 
  but 
  it 
  does 
  not 
  follow 
  that 
  they 
  are 
  close 
  to 
  the 
  central 
  

   point 
  of 
  the 
  system. 
  The 
  mean 
  distribution 
  table 
  (Table 
  I) 
  was 
  

   prepared 
  chiefly 
  as 
  a 
  means 
  of 
  studying 
  how 
  the 
  stars 
  crowd 
  together 
  

   toward 
  the 
  Milky 
  Way. 
  In 
  order 
  to 
  smooth 
  out 
  local 
  irregularities 
  

   in 
  distribution 
  as 
  much 
  as 
  possible, 
  counts 
  all 
  around 
  the 
  sky 
  in 
  the 
  

   Milky 
  Way, 
  and 
  in 
  circles 
  parallel 
  to 
  the 
  Milky 
  Way, 
  were 
  combined 
  

   into 
  single 
  averages, 
  one 
  for 
  each 
  latitude; 
  further, 
  the 
  results 
  for 
  

   the 
  two 
  halves 
  of 
  the 
  sky 
  were 
  also 
  averaged. 
  This 
  procedure 
  was 
  

   well 
  suited 
  to 
  the 
  purpose 
  then 
  in 
  view, 
  and 
  led 
  to 
  the 
  conclusions 
  

   already 
  stated. 
  But 
  now 
  we 
  must 
  see 
  if 
  the 
  averaging 
  process 
  has 
  

   concealed 
  anything 
  of 
  importance. 
  

  

  This 
  inquiry 
  has 
  point 
  because 
  it 
  is 
  known 
  that 
  the 
  stars 
  are 
  not 
  

   equally 
  numerous 
  in 
  all 
  parts 
  of 
  the 
  Milky 
  Way. 
  The 
  irregularity 
  

   meant 
  is 
  not 
  the 
  rapid 
  fluctuation 
  in 
  numbers 
  shown 
  by 
  the 
  cloud-like 
  

   grouping 
  of 
  stars, 
  but 
  a 
  more 
  fundamental 
  difference 
  revealed 
  by 
  the 
  

   exceptional 
  size 
  and 
  richness 
  of 
  the 
  star 
  clouds 
  in 
  the 
  general 
  direction 
  

   of 
  Sagittarius 
  as 
  compared 
  with 
  those 
  in 
  the 
  opposite 
  part 
  of 
  the 
  sky. 
  

   Because 
  of 
  this 
  difference, 
  it 
  has 
  often 
  been 
  suggested 
  that 
  the 
  solar 
  

   system 
  may 
  indeed 
  be 
  at 
  some 
  distance 
  from 
  the 
  central 
  point 
  of 
  the 
  

   system. 
  If 
  so, 
  slow 
  progressive 
  changes 
  should 
  appear 
  in 
  the 
  counts 
  

   along 
  the 
  Milky 
  Way, 
  and 
  in 
  fact, 
  along 
  any 
  parallel 
  circle, 
  up 
  to 
  a 
  

   high 
  galactic 
  latitude. 
  We 
  therefore 
  turn 
  again 
  to 
  the 
  original 
  counts 
  

   in 
  order 
  to 
  see 
  whether 
  they 
  show 
  any 
  such 
  change 
  when 
  these 
  circles 
  

   are 
  followed 
  around 
  the 
  sky. 
  

  

  In 
  studying 
  the 
  crowding 
  of 
  stars 
  toward 
  the 
  Milky 
  Way, 
  we 
  con- 
  

   centrated 
  attention 
  on 
  this 
  one 
  feature 
  of 
  the 
  distribution 
  by 
  dealing 
  

   with 
  the 
  average 
  of 
  the 
  counts 
  in 
  all 
  longitudes. 
  This 
  eliminated 
  any 
  

   influence 
  arising 
  from 
  the 
  possible 
  progressive 
  change 
  with 
  longitude 
  

   in 
  which 
  we 
  are 
  now 
  interested. 
  And 
  now 
  we 
  avoid 
  any 
  disturbance 
  

   which 
  might 
  arise 
  from 
  the 
  crowding 
  toward 
  the 
  Milky 
  Way 
  by 
  com- 
  

   paring 
  only 
  counts 
  of 
  stars 
  in 
  the 
  same 
  latitude, 
  and, 
  of 
  course, 
  to 
  the 
  

   same 
  limit 
  of 
  brightness. 
  A 
  simple 
  procedure 
  is 
  to 
  compare, 
  for 
  a 
  

   given 
  latitude, 
  the 
  number 
  of 
  stars 
  actually 
  counted 
  in 
  each 
  region 
  

   with 
  the 
  average 
  number 
  for 
  the 
  whole 
  circuit 
  of 
  the 
  sky, 
  and 
  then 
  

   to 
  see 
  whether 
  the 
  differences 
  show 
  any 
  progressive 
  variation. 
  

   Finally, 
  to 
  test 
  the 
  results 
  we 
  may 
  make 
  independent 
  comparisons 
  for 
  

   several 
  different 
  latitudes 
  and 
  for 
  a 
  number 
  of 
  limits 
  of 
  brightness. 
  

  

  Figure 
  1 
  illustrates 
  the 
  results 
  for 
  the 
  stars 
  brighter 
  than 
  the 
  six- 
  

   teenth 
  magnitude, 
  in 
  general 
  for 
  every 
  10° 
  up 
  to 
  latitude 
  70° 
  on 
  either 
  

  

  