USSPS Codes

Code USSPS is used to describe sunspot groups.

Example:

Definition of symbols:

  • USSPS comes from SunSPotS

  • I I I I I = station indicator

  • DD = UT day of observation
  • HHH = UT time of observation in hours and tenths of hour

  • a a a = relative sunspot number
  • b = seeing quality
    • 1 = very poor
    • 2 = poor
    • 3 = fair
    • 4 = good
    • 5 = exceptional
  • c = solar disk size used for measurement
    • 1 = diameter of the solar disk less than 15 cm
    • 2 = diameter of the solar disk between 15 and 30 cm
    • 3 = diameter of the solar disk more than 30 cm
    • 4 = individual sunspot groups at very high resolution

  • d d = serial number of sunspot group
  • AAA = area of sunspot group in tens of millionths of the solar hemisphere

  • Q = quadrant (heliographic coordinates) in geometric center of sunspot groups is located
    • 1 = NE (northeast)
    • 2 = SE (southeast)
    • 3 = SW (southwest)
    • 4 = NW (northwest)
  • XX = distance to the central meridian in degrees
  • YY = heliographic latitude in degrees

  • f = type of penumbra in the largest spot in group (Modified Zurich (McIntosh) Sunspot Classification)
    • 0 = no penumbra (Zurich class A or B)
    • 1 = rudimentary (r)
    • 2 = small symmetric (s) north to south diameter < 2.5°
    • 3 = small asymmetric (a) north to south diameter < 2.5°
    • 4 = large symmetric (h) north to south diameter > 2.5°
    • 5 = large asymmetric (k) north to south diameter > 2.5°
  • g = relative importance of the leading spot and density of the sunspot population
    • 1 = leading spot largest and sunspot population density open
    • 2 = following spot largest and sunspot population density open
    • 3 = leading and following spots nearly same size and sunspot population density open
    • 4 = leading spot largest and sunspot population density intermediate
    • 5 = following spot largest and sunspot population density intermediate
    • 6 = leading and following spot nearly same size and sunspot population density intermediate
    • 7 = leading spot largest and sunspot population density compact
    • 8 = following spot largest and sunspot population density compact
    • 9 = leading and following spot nearly same size and sunspot population density compact

Note: g = / (slant line) for unipolar spots of Zurich class A, H or J

  • h = Zurich or McIntosh modified sunspot class
    • 1 = A
    • 2 = B
    • 3 = C
    • 4 = D
    • 5 = E
    • 6 = F
    • 7 = G
    • 8 = H
    • 9 = J

Note: If the above McIntosh f and g subtypes are given, for consistency with the Modified Zurich (McIntosh) Sunspot Classification, G and J types should then not be used. Normally G will be encoded as an open E or F and J will be encoded as a small H.

  • ii = Number of spots in the group