groupProj. UProj. WSCorr. UCorr. WS BLLCMPos. angler

2297 31 162 22 112 28.50 146.40 40.80 303.40 0.6880


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Greenwich Photoheliographic Results 1891-09-12 09:47:01 UT

No observation available


spotProj. UProj. U+PCorr. UCorr. U+PBLLCMPos. angler

1 31 162 22 112 28.50 146.40 40.80 303.40 0.6880


  • Proj. U -  Projected umbra area in millionths of solar disc, negative values indicate
    that the umbra consists of fragmented regions which cannot be separated without losing umbral area.
    In this way several spots (intensity minima in the umbra) have a common umbra, e.g. -2 means that
    the given spot shares an umbra with spot No.2, and the common U value is indicated at spot No.2.
  • Proj. WS -  Projected whole spot area in millionths of solar disc, negative values indicate
    that several umbras have a common penumbra, e.g. -7 means that the given umbra shares
    a penumbra with umbra No.7, and the WS value is indicated at No.7.
  • Corr. U -  Corrected umbra area in millionths of solar hemisphere, for negative values see above
  • Corr. WS -  Corrected whole spot area in millionths of solar hemisphere, for negative values see above
  • B -  Heliographic latitude B; positive: North, negative: South
  • L -  Heliographic longitude L
  • LCM -  Longitudinal distance from the Sun's central meridian
  • Pos. angle -  Position angle
  • r -  Distance from the centre of Sun's disc in terms of Sun's radius