2739
Alpha
13
13
  • Area = 18
  • Zurich = H
  • Penumbra = large symmetric (h) north to south diameter > 2.5
  • Leading =
  • NN = 2
14
14
  • Area = 2
  • Zurich = B
  • Penumbra = no penumbra (Zurich class A or B)
  • Leading = 1
  • NN = 5

Catania sunspot groups
2019-04-18 06:18:00
NOAA AR/sunspot
NOAA Halpha plage
NOAA expected region
2019-04-21 00:30:00
PROBA2/SWAP 17.4nm
2019-04-21T01:57:07.035