USSPI and USSPY Codes

Code USSPI is used to describe sunspots classified by magnetic characteristics.
Code USSPY is used to describe sunspots classified by magnetic field gradient.
In these codes sunspot groups are classified into four different types: UNIPOLAR, BIPOLAR, CONFIGURATION, and MUTIPOLAR (or COMPLEX) region.
The two codes are identical, except that code USSPY has one 5-digit group added to the end of the CONFIGURATION description. The extra group is used to describe the intensity and strength of the magnetic field in gauss.

Example of USSPI codes:

  • Unipolar

  • Bipolar

  • Configuration:

Example of USSPY codes:

  • Configuration:

Definition of symbols:

  • USSPI comes from SunSPots, code I
  • and

  • USSPY comes from SunSPots, code Y

  • I I I I I = station indicator

  • DD = UT day of observation
  • HH = UT hour of observation
  • G = quality of the seeing
    • 1 = very poor
    • 2 = poor
    • 3 = fair
    • 4 = good
    • 5 = exceptional
  • If basically UNIPOLAR use the following two codes:

  • Q = quadrant (heliographic coordinates) in which geometric center of sunspot group 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

  • K = key number
    • 5 = isolated unipolar spot or large spot surrounded by small companions of opposite polarity (configurationB)
  • a = Zurich sunspot class
    • 1= A
    • 8 = H
    • 9 = J
  • b = diameter of the main spot umbra in degrees
  • c = magnetic polarity of the main spot
    • 1= north
    • 2 = south
    • 3 = doubtful because of its heliographic longitude)
  • d = configuration
    • 0= not any configuration; that is single spot or all tiny sports
    • 1 = several tiny spots of opposite polarity at a distance (configuration B)
    • 2 = configuration B suspected according to chromospheric data (dark filament surrounding the spot like an eyebrow)
  • If BIPOLAR use the following three codes:

  • Q = quadrant (heliographic coordinates) of geometric center of bipolar group
    • 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

  • K = key number
    • 6 = open bipolar (the shortest distance between the edges of the main spots is equal to or greater than the diameter of the largest spot)
    • 7 = closed bipolar (simple classical bipolar group and the shortest distance between the closest main spots is less than the diameter of the largest spot in the group)
  • a = Zurich sunspot class
    • 2 = B
    • 3 = C
    • 4 = D
    • 5 = E
    • 6 = F
    • 7 = G
  • b b = longitude difference in degrees between exterior edges of the main spots
  • c = number of 5-digit blocks used to describe configuration, if any configuration exists, or X when this bipolar group is part of a multipolar region (see K = 8)

  • d d = shortest distance in degrees between the interior edges of the closest spots of opposite polarities
  • e = diameter in degrees of the largest spot umbra
  • f = orientation of the inversion (neutral) line:
    • 1 = the inversion line is roughly parallel (30_) to a solar meridian and the two main spots are equivalent (Beta) or the leading spot is the larger (Beta P)
    • 2 = the inversion line is roughly parallel (30_) to a solar meridian but the following main spot is the larger (Beta F)
    • 3 = the inversion line is tilted between 30_ and 60_ to the solar equator and the two main spots are equivalent, or the leading spot is the larger (Beta and Beta P)
    • 4 = the inversion line is tilted between 30_ and 60_ to the solar equator but the following main spot is the larger (Beta F)
    • 5 = the inversion line is roughly parallel (30_) to the solar equator and the two main spots are equivalent, or the leading spot is the larger (Beta and Beta P)
    • 6 = the inversion line is roughly parallel (30_) to the solar equator but the following main spot is the larger (Beta F)
  • g = description of the polarities
    • 1 = the polarities are normal in relation to the hemisphere and solar cycle
    • 2 = the polarities are normal but with many tiny spots
    • 3 = the polarities are reversed in relation to the hemisphere and solar cycle
    • 4 = the polarities are reversed but with many tiny spots
    • 5 = the two polarities are nearly at the same longitude (see f = 5 or 6)
  • If CONFIGURATION exists use the following two codes (USSPI) or three codes (USSPY):

Note: CONFIGURATION exists if two spots or many more spots of opposite polarities are very near together (for example, the distance between the interior edges of the main spots is less than or equal to the diameter of the biggest spot). The best known is the Delta configuration, where two umbra of opposite polarities are in the same penumbra (these are used to estimate the position of the highest gradient of the longitudinal magnetic component).

  • Q = quadrant (heliographic coordinates) of geometric center of an active configuration where
    • 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

  • K = key number
    • 0 = description of active configuration
  • h = type of configuration and orientation of the inversion line
    • 1 = a spotted configuration and the inversion line is roughly parallel (30_) to a solar meridian
    • 2 = a spotted configuration and the inversion line is titled between 30_ and 60_ to the solar equator
    • 3 = a spotted configuration and the inversion line is roughly parallel (30_) to the solar equator
    • 4 = a Delta configuration and the inversion line is roughly parallel (30_) to a solar meridian
    • 5 = a Delta configuration and the inversion line is tilted between 30_ and 60_ to the solar equator
    • 6 = a Delta configuration and the inversion line is roughly (30_) parallel to the solar equator
  • i = diameter in degrees of the west spot (the west umbra in a Delta configuration)
  • j = diameter in degrees of the east spot (the east umbra in a Delta configuration)
  • k = distance in degrees between the interior edges of the two polarities (the two umbrae in a Delta configuration). For two polarities nearly at the same longitude there is no special order to report the spot or umbra diameters.
  • Include the following group when using code USSPY:

  • l l = intensity of north polarity field (gauss divided by 100)
  • m m = intensity of south polarity field (gauss divided by 100)
  • n = evaluation of the strength of the magnetic field gradient according to the following
    • 1 = weak (n < 0.1 gauss/km)
    • 2 = large (0.1 gauss/km < n < 0.5 gauss/km)
    • 3 = very large (n > 0.5 gauss/m)
  • If MULTIPOLAR or COMPLEX region made up of several UNIPOLAR or BIPOLAR GROUPS, use the following two codes, followed by the appropriate UNIPOLAR, BIPOLAR or CONFIGURATION groups:

  • Q = quadrant (heliographic coordinates) of geometric center of the region
    • 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

  • K = key number
    • 8 = multipolar region which can be reported as comprising a set of unipolar and (or) bipolar groups and active configurations
    • 9 = complex region
  • a a = longitude difference in degrees between exterior edges of the main spots
  • b b = latitude difference in degrees between exterior edges of the main spots
  • The above two groups are followed by the appropriate groups:

  • QXXYY K a b c d as defined under UNIPOLAR (p. 2 - 6)
  • QXXYY K a b b c d d e f g as defined under BIPOLAR (p. 2 - 7)
  • QXXYY k h i j k l l m m n as defined under CONFIGURATION (p. 2 - 8)

Note: / is to be used for data not available.