Former NASA astronaut John Grunsfeld, now associate administrator of NASA's Science Mission Directorate, told an astronomical gathering in Austin, Texas, that political demarcations between countries are sometimes visible from orbit in the form of environmental and infrastructure differences.
"Wealthy countries are lined in green and then you see the country next door that has no water," Grunsfeld said last week at the 219th meeting of the American Astronomical Society.
Differences in the amount of electric lighting visible at night and variation in forestation patterns can also outline national boundaries, he said.
"The big thing is, no matter where I was on planet Earth, what you see is we are changing the planet," Grunsfeld said.
Grunsfeld was a crew member on five space shuttle missions, including three visits to service the Hubble Space Telescope, SPACE.com reported.
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