Fig. 4
From: A review of unusual VLF bursty-patches observed in Northern Finland for Earth, Planets and Space
Long lasting ‘wands’ VLF bursty-patches at KAN. Power spectrum density at KAN on 23 December 2020 from 04:00 to 08:00 UT (05:30–09:30 MLT) and from 07:44 to 07:47 UT, between 0 and 10 kHz. Dashed and dotted horizontal white lines show, respectively, the local equatorial 0.5 fce and fce for the L-shell of KAN. Through this panel we see multiple frequency-elongated VLF bursty-patches mostly for 6 < f < 8 kHz. As examples, some of these ‘wands’ are indicated with black angle arrows to make them more noticeable to the reader