Day and Night Map
Change the date and time to see where Earth is in daylight, darkness or twilight.
Learning guide
What you’ll learn
Explain how Earth’s rotation produces day and night.
What to change
Choose a date and time. Use Now to return to the present.
Drag the slider to choose a time in the year. The arrow buttons move one day at a time. Play runs through the year. The seasonal buttons let you compare the daylight pattern at equinoxes and solstices.
What to observe
Find a place in daylight and another in darkness. Watch the boundary move as time changes.
Why it happens
Earth rotates, bringing places into sunlight and then turning them away.
Reading the map
The map shows which parts of Earth face the Sun at the selected time. Bright areas show daylight. Dark areas are places where the Sun is below the horizon. The band between them shows twilight.
The yellow marker shows where the Sun is directly overhead, called the subsolar point. The Moon marker shows where the Moon is overhead and its phase at the selected time. The dashed gold lines mark the tropics. The boundary between day and night is called the terminator.
Questions answered
Why does night happen? Your part of Earth faces away from the Sun.
What is twilight? Sunlight scattered through the atmosphere lights the sky while the Sun is below the horizon.
Can the Moon appear during daylight? Yes. The Moon can be above the horizon during the day as well as at night.
Teacher notes
Learning objective: Explain the changing daylight pattern using Earth’s rotation.
Suggested ages: 9–14. Adapt the activity to your group.
Suggested duration: 10 minutes.
Prerequisite knowledge: Earth is a rotating globe.
Common misconception: The Sun circles Earth each day. The daily change between daylight and darkness is caused by Earth rotating.
Sources: Read our methods and data sources and NASA’s explanation of a day.
Model limitations: Flattening Earth into a rectangular map distorts shapes and distances, especially near the poles. Sun and Moon markers are enlarged for visibility. The map illustrates sunlight geometry; local terrain and weather affect what you see.
Lesson status: Ages and duration are suggestions, not classroom-tested results. Lesson development and unfinished drafts are separate.
The Sun is overhead at 4.2° S, 144.9° W. This is the subsolar point. Days are getting shorter in the Northern Hemisphere as Earth travels around the Sun. Earth’s axis keeps pointing in nearly the same direction.
Map limitation: Earth is a globe flattened into a rectangle, so shapes and distances — especially near the poles — are distorted. The Sun and Moon markers are enlarged so you can see them.