Lowest position of the sun on the summer solstice in the northern hemisphere (demonstrates different types of twilight and that above 48° north it does not get fully dark) [OC]
from /r/dataisbeautiful
北半球の夏至における太陽の最低位置(さまざまな種類の薄明かりと、北緯48°以上では完全には暗くならないことを示す) [OC].