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Day/Night Clock

See where in the world its day and night.

Run the code to make a map showing where its day and night right now:

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Make a world map:

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Shade the portion of the world where its currently night with gray:

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Make a map showing where it will be day and night in 8 hours. Try other times:

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Now gives the current date and time:

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Get the date and time in 8 hours. To enter the time, type += to get a natural language input box and type 8 hours:

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Show where it will be night in 8 hours:

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Show both now and in 8 hours together. Try other colors, like Orange or Green:

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Show two different night hemispheres by putting them in a list, indicated by curly brackets ({}):

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Make the later night hemisphere blue so you can tell it apart from the current one:

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Use a different map projection. Try other projections, like Albers, Robinson, or Mercator:

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World maps necessarily distort shapes because the curved surface of the world has to be flattened out. There are various ways to flatten the Earth, called projections. Specify which projection to use:

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Different projections give different kinds of distortions:

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Share ItMake a website that shows the current day/night map:

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Deploy the day/night map code to the Wolfram Cloud where anyone with a browser can use it:

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Click the link in the output to visit the site.

Share the link by right-clicking it and choosing Copy Address. Paste the link into an email, tweet, or other message.

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