Yesterday will mostly be remembered as a momentous day in American politics. But it also happened to be an important milestone in human spaceflight (and, arguably, our evolution as a spacefaring species): As of Nov. 2, 2010, astronauts have lived and worked in space continuously — aboard the International Space Station — for an entire decade.
To mark the occasion, NASA released this stunning picture taken through a window of the ISS as the station was passing over the Gulf coast of the United States. (Click on the image to go to the NASA image gallery, where you can see it blown up even larger.)
In the image, New Orleans is the bright splotch just above the solar panel of the Soyuz spacecraft, which is docked to the station. The dark spot to the left (north) of the city, is Lake Ponchartrain. And the Alabama coast extends beyond New Orleans, up and to the left a bit. (Note: NASA’s caption incorrectly identifies New Orleans as Mobile, Alabama, which is actually above The Crescent City on the Gulf Coast in this image.)
The glowing ribbon of light extending toward the upper right from New Orleans actually is Louisiana’s Route 23, which protrudes into the Delta along the Mississippi River. And Houston is the bright patch that’s partially obscured by an instrument sticking out from the Soyuz spacecraft. The coast extends behind the spacecraft, and then curves around into Mexico, where some city lights are visible at the limb of the Earth (bottom of the picture).
I’m really struck by three things in this image.
The first is the numerous pinpoints of light out in the Gulf of Mexico (to the right in the image, before the grayish/blueish cloud bank). Are these the lights of oil platforms in the Gulf? I’m not positive, but I think so. (What else could they be?)
I’m also struck by the band of warmish color that extends around the limb of the Earth. Is this the atmosphere lit up by fading sunlight or maybe even the glowing lights of cities below? Again, I’m not sure, but I think this is a very good bet.
If I’m correct, that thin band highlights something that many people still have a hard time believing: the fact that we puny human beings are actually capable of altering the composition of the atmosphere so profoundly that we can influence one of our planet’s life support systems: the Earth’s themostat. (I’m speaking, of course, of the carbon cycle, which controls the amount of heat-trapping carbon dioxide in the atmosphere.)
From this perspective, the atmosphere doesn’t seem quite so thick — and perhaps not quite so resistant to our influence — as it does when we simply look straight up from the ground.
Perhaps most striking, at least aesthetically, is our footprint on the land. It is revealed not only by the large cities but also the necklaces of glimmering highways that connect them. It takes fossil fuels to keep all of this alight, and it is by burning those fuels that we affect the composition of that brownish band.
It’s true that we’ve seen Earth-at-night images before. But there is something about this one that is particularly arresting, at least for me. And most important is this: It’s one thing to read in a scientific paper that human activity has transformed up to 50 percent of the Earth’s surface. It’s another thing entirely to actually see that number lit up in such a dazzling way.