Day and Night: Changes During the Day
This visual allows you to investigate the appearance of day and night over a 24 hour period using the image of a flat map and of a globe. To investigate, place your cursor on the globe, click and drag. The questions below are used to assist you in your observations.
This visual shows the appearance of the earth on June 21st. The globe is oriented so that the equator is horizontal. The time of day is given in GMT (Greenwich Mean Time, or the time at the prime meridian). The observer viewing the globe is directly over 0 latitude 0 longitude.
Note how the time changes as the image is manipulated. What direction does the earth rotate (using the north pole as reference - does it rotate clockwise or does it rotate counterclockwise?)
Where on earth is daylight during the entire 24 hour day on this date?
Where on earth is darkness during the entire 24 hour day on this date?
Which location has the longest time of daylight on this date: Washington DC or Perth Australia?
If one city on a given meridian (line of longitude) is in daylight at an instant in time, are all cities on this meridian in daylight?
Is the duration of daylight different for locations on the same latitude (parallel) on a given date?
What is the cause for the different durations of daylight at different latitudes on the earth?
Copyright 1999 John C. Park for Science Junction
Still images of Earth ©1999 The Living Earth, Inc.