The invention of the light bulb some 140 years ago was such an advancement for humanity that it’s apparent from space.
A new e-book from NASA, “Earth at Night,” illustrates this and other phenomena with 25 years’ worth of satellite photos. In particular, it shows how major holidays change lightscapes around the world.
Download the e-book here, and see some select images in the gallery below.
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NASA researchers found nighttime lights in the U.S. shine up to 50% brighter in December due to holiday light displays. The green pixels in these satellite images from 2012—2013 show increased light usage in December. Yellow pixels indicate areas with small changes in light use; red indicates less usage.
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The cluster of more intense light can be seen around such southeastern U.S. cities as Atlanta and Charlotte. “Lights in the central urban areas did not increase as much as in the suburbs but still brightened by 20 to 30 percent,” NASA says.
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NASA says these images provide “a new way to understand the broad societal forces impacting energy decisions.”
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Yellow patterns in Florida indicate little change in light usage in December.
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Green patterns indicating higher light usage can be seen over the southwestern cities of Los Angeles, San Diego, Las Vegas and Phoenix.
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A similar change in light usage can be seen here over Cairo during the holy month of Ramadan. “The change made sense because Muslims fast during daylight in Ramadan, pushing meals, social gatherings, commerce, and other activities into nighttime hours,” NASA noted.
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“Peaks in light use closely tracked the Islamic calendar, as Ramadan shifted earlier in the summer each year,” NASA says.
