# DOI: https://doi.org/10.5880/Kp.0001 # LICENCE: CC BY 4.0, please cite: # Matzka, J., Bronkalla, O., Tornow, K., Elger, K. and Stolle, C., 2021. # Geomagnetic Kp index. V. 1.0. GFZ Data Services, # https://doi.org/10.5880/Kp.0001 # Matzka, J., Stolle, C., Yamazaki, Y., Bronkalla, O. and Morschhauser, A., # 2021. The geomagnetic Kp index and derived indices of geomagnetic activity. # Space Weather, https://doi.org/10.1029/2020SW002641 # The Kp index was introduced by Bartels (1949) and is produced by Geomagnetic # Observatory Niemegk, GFZ German Research Centre for Geosciences. International Quietest Days Most Disturbed Days Month Q1 Q2 Q3 Q4 Q5 Q6 Q7 Q8 Q9 Q10 D1 D2 D3 D4 D5 Jan 2005 26 27 25 9K 6 10 28K 24A 11A 13A 18 17 21 19 2 Feb 2005 5 23 4 15 13 22 12 24K 1K 14 18 8 7 9 10 Mar 2005 4 22 12 20 23 15 28 3 29 24 7 6 8 9 25 Apr 2005 10 27 26 28 21 2 9 8 17 1 5 13 12 30 4 May 2005 26 27 25 24 5 6 23 4 14 2A 30 8 15 16 1 Jun 2005 21 10 20 28 27 8 19 9 11 29 23 12 13 16 4 Jul 2005 6 24 5 25 8 26 4 23 15 7 10 12 13 9 28 Aug 2005 11 20 30 12K 28 27 19 15K 26K 8 24 31 6 25 13* Sep 2005 24 21 20 25K 8 23K 22 19 29A 6A 11 12 15 13 2 Oct 2005 15 12 23 20 14 21 5 4 29 6 8 25 31* 2* 17* Nov 2005 16 27 10 8 17 9 15 18 21 26 3 4 13* 6* 30* Dec 2005 23 7 8 6 15 5 14 18 17 24 11 28* 27 1* 20*