Why Does the Sun "Rise" and "Set"? Exploring the Earth's Daily Cycle This animation shows how sunlight changes as the Earth rotates on its axis. Each of the 4 frames is one hour later. Look closely at the lines separating daylight and darkness. Then answer the questions below. Images courtesy of Living Earth What do you notice? 11:00 GMT: What do you think you were doing then? What changed between 11:00 GMT and 12:00 GMT? What do you think caused it? 13:00 GMT: What have people on the East Coast of the United States just experienced? 14:00 GMT: In what country (or part of the world) might people be eating dinner? NEXT: Find out what scientists say >>. * The time is shown as "GMT," or Grenwich Mean Time. This is also known as "UT," or Universal Time. It is the same moment everywhere on earth when times are given as UT or GMT. Learning Standards >> This Season Teachers Kids Orientation Registration Search Copyright 1997-2008 Journey North. All Rights Reserved. Questions or comments? Contact us.