Fig. 5From: Simultaneous observations of equatorial plasma bubbles with an all-sky airglow imager and a HF Doppler sounding system in TaiwanDetailed comparison between the sub-structures of OSS and the branches of EPB for Event 3. a A 630.0 nm airglow image at 17:13 UT on March 16, 2015, mapped onto the geographic coordinate system. b The Doppler spectrogram obtained between 15:00 and 19:00 UT on March 16, 2015. c The longitudinal keogram extracted at the latitude of RP2Back to article page