The yellow dots are aircraft. It is a 24 hour observation of all of the large aircraft flights in theworld, condensed down to about 2 minutes. You can tell it was summertime in the north by the sun's footprint over the planet. You could seethat it didn't quite set in the extreme north and it didn't quite rise inthe extreme south. Notice that as evening approaches, the traffic is predominantly from the USto Europe and when daylight comes, the traffic switches and itis predominantly from Europe to the US.