This photograph is 40 years old.
Let that sink in for a moment.
It’s called “The Blue Marble”, and it was taken by the crew of Apollo 17 as they looked back on their home on their way to the Moon, exactly 40 years and three days ago.
You’ve probably seen this photo a few times. It’s inspired many modern replicates, from this year’s "Blue Marble 2012" to the just-released view of Earth at night, the "Black Marble". It’s understandably hard to pick a favorite. Look at how wonderful they all are:
For me, it’s not a tough decision. Blue Marble 1972 was the first, and it is the finest in my heart. It may not have the detailed resolution, or the rich color, or the exotic shading that comes from a modern digital composite image drawn from the whole electromagnetic spectrum. But it marks a pivotal moment in mankind’s history.
Apollo 17 wasn’t the first mission to the Moon, of course. It was the last. That’s what makes this photo so special. These pioneers, these explorers, they turned their Hasselblads back toward home and snapped this shot. These interplanetary adventurers (the Moon likely used to be a dwarf planet, so they’ve earned the title) put our existence in perspective with one click.
A human being hasn’t seen this sight with the naked eye since 1972. The International Space Station doesn’t orbit far enough from Earth to see anything but curved edges. Same with the shuttle. Perhaps Curiosity, had its eye been somehow deployed in mid-flight, could have turned back to see where it came from. But alas, no.
I’m happy with the images of Earth that our satellites send back. Not one, but two of them grace my iPhone’s wallpapers (“Aqua” and “Black” marbles, if you’re interested), that phone that has more computing power than the entire spacecraft this photo was taken from. But I want another human being to see our Earth from this vantage point.
When this image came back to Earth, people stopped for a moment, however brief, in the midst of wars Cold and hot, to realize this is our home. Our home. Maybe a military officer somewhere thought twice about dropping bombs that day. Maybe a parent showed it to their kids before bed instead of sitting silently in front of the TV. Maybe someone who was alive when the Wright brothers flew for the first time smiled at how far we’d come.
I don’t want this to be the last time we feel those things. Let’s go take another picture.