Fig. 1From: First imaging and identification of a noctilucent cloud from multiple sites in Hokkaido (43.2–44.4°N), JapanLocations and fields of view (FOVs) of cameras at five sites in Hokkaido. FOVs shown in this figure are estimated by assuming the altitude of a cloud layer to be 85 km with no obstacles (e.g., trees, mountains, buildings) over the horizon. The blue triangle shows the location of Wakkanai VHF and MF radarsBack to article page