Egypt's Nile River delta in 1992 (left) and 2009 (right)

A new study by Swiss researchers at ETH Zurich finds explosive development in many parts of the world -- and lots of other twinkly signs that the earth’s economic center has, according to the study, moved east.

The study, published earlier this week, looked at satellite images of nighttime lights since such records were first digitized in 1992. They posit that electricity correlates with wealth, which suggests some dramatic changes in the developing world from then until 2009.

Consider these images from the Shanghai region in 1992 and 2009. Shanghai’s growth is, of course, legend: The city’s population grew by 6 million people from 2000 to 2010 alone and its GDP has grown by double-digits every year for 20 consecutive years. That definitely comes through in these satellite shots:

Shanghai and surrounding region in 1992 (left) and 2009 (right)

The study also found huge growth in Egypt (especially around the Nile River, pictured above), India and Brazil, as well as growing light disparities across the globe. Some of the lighter and dimmer areas have grown both in size, and have grown brighter and dimmer, respectively. This is perhaps a sign of urbanization, as people in less-lit rural areas continue to move into bright urban areas.

There are some anomalies, of course: A number of bright cities in Russia, Ukraine, the U.K. and Canada show marked dimming over time. The authors attribute that to shrinking urban populations (cities like Dnipropetrovsk and Nizhniy Novgorod dominated the U.N.’s most recent cities report) and light pollution programs (Canada and the U.K. boast prominent ones).

But, overall, the lights seem to signal economic changes. The researchers calculate that the planet’s “mean center of light” has shifted east and south at roughly 27 miles a year over the past 20 or so years, moving roughly from Granada, Spain to Laghouat, Algeria, as China, India and Africa grow brighter.

That matches a 2012 study by the McKinsey Global Institute that found the earth’s economic center had moved southeast, as well.