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On the above animation, each dot represents one airplane. The three main markets are North America, Europe and Pacific Asia, each operating mostly during their respective daylight hours, implying that the global air transport system is constantly active. Transatlantic flights are also significant with the flights leaving Europe westbound mostly in the morning and the afternoon so that they can arrive in North America only a few hours later in local time due to time zone differences. Eastbound flight to Europe mostly leave North America in the evening so that they can arrive in Europe in the early morning.