The Only World We’ve Got

It’s a story repeated endlessly throughout human history; violence and bloodshed over swathes of land or sea which for some reason become important to a group of people, important enough to kill over.  Each group feels certain their cause is righteous and just, and most of them think their cause is eternal too.  But not long after, it will be a different cause, fighting over slightly different borders, every bit as convinced that this time it is right and should be for always.

Holy Land, Then and Now

Borders that shift like the desert sands, whole countries whose names and affiliations change again and again are fought over as if they are something objectively real and forever.  Yet they are arbitrary, and ephemeral, and a thousand years later the old names are little more than rumor.  So we pull the camera out a bit, and those tenuous borders disappear:

Mideast as seen by the MODIS instrument on NASA's Terra spacecraft

Mideast as seen by the MODIS instrument on NASA’s Terra spacecraft

If you look closely, you can still see the signs of human habitation.  Curiously straight lines across the desert, lines which are themselves fought over as vital conduits for supplies across a forbidding landscape.  Human habitation is even more obvious when you look at night:

The mideast, at night, as viewed from the International Space Station, with airglow visible above the limb of the Earth.

The Mideast, at night, as viewed from the International Space Station, with airglow visible above the limb of the Earth.

But even with the lights to tell you where the people are, outlining the Mediterranean coastline, we now cannot see borders.  Israel runs straight into Jordan and Jordan runs into Syria and you can’t tell where the one stops and the next begins.  But you can still tell where the major population centers are, with the Nile Delta in Egypt being especially prominent.  So let’s zoom out a bit more.

The Mideast and northeast Africa as seen by the Galileo spacecraft during its Earth gravity assist maneuver en route to Jupiter.

The Mideast and northeast Africa as seen by the Galileo spacecraft during its second and final Earth gravity assist maneuver en route to Jupiter.

Human habitation is no longer visible.  Galileo’s sensitive instruments were able to detect signals in the atmosphere consistent with life (a proof-of-concept exercise done to assist in the search for life on other worlds) but could not even narrow it down to the difference between plants and animals, or even bacteria.  At this point, our world is still very recognizable, but humanity isn’t.  Still we fight, as we forget that all this is part of….

Full-disk image of Earth, centered on Africa, taken during Galileo's first Earth gravity assist maneuver.

Full-disk image of Earth, centered on Africa, taken during Galileo’s first Earth gravity assist maneuver.

…an entire landmass.  No one has ever ruled all of Africa, and even the Mideast has defied most attempts at unification.  Yet geologically, it is all one place.  It is unzipping in places, on either side of the Arabian Peninsula and down the Great Rift Valley of Africa, but for now it is still very much a single landmass, conjoined with Eurasia, and has been for the entire history of our young species.  Still, we seem to revel in sorting our species out into groups, and Africans are certainly given their own group an awful lot of time, just for the coincidence of coming from here.  Yet we must continue to zoom out.

Earthrise from Apollo 8

Earthrise from Apollo 8

An educated guess tells me that might be the eastern coast of South America poking out, but mostly this image shows ocean.  Well, not mostly — far more of the image is taken up by the surface of the Moon, looming large in the foreground while the Earth is relegated to a position we find more familiar as a Moonrise.  Here, a quarter of a million miles away, it is very difficult to make out even the continents with the unaided eye.

Earth and Moon captured together for the first time in a single frame by Voyager 1, during its departure from the system in 1977.

Earth and Moon captured together for the first time in a single frame by Voyager 1, during its departure from the system in 1977, at a distance of over 7 million miles.

Continents are no longer recognizable; the NASA release for this image tells us that Asia is directly below in this picture, but we must take their word for it.  The most prominent features are the clouds and the seas, Earth’s vast blue oceans teeming with life.  For yes, though we recognize the land as our home, most of Earth’s life is actually in the water.  Still we zoom out.

Telescopic view of Earth and Moon from Mars, as seen by Mars Reconnaissance Orbiter's HiRISE instrument.

Telescopic view of Earth and Moon from Mars, as seen by Mars Reconnaissance Orbiter’s HiRISE instrument.

Seeing continents is now hopeless even with a half-meter aperture telescope.  Earth was as close as it could usefully be and still get this image — a mere 88 million miles.  (Closer and it would be too close to the Sun to photograph safely with MRO’s main camera, which is not designed to point close to the Sun.)  This is our world.  OUR world.  You can’t see the things we fight over.  Any trace of them is now lost.  But at least you can still see what makes it great — water, atmosphere, weather, life itself.

But here’s how it looks without magnification:

MSL Curiosity image of Earth and Moon in the night sky over Gale Crater on Mars.

MSL Curiosity image of Earth and Moon in the night sky over Gale Crater on Mars.

That’s our world from the surface of an alien planet.  We’re a bright evening star (and occasional morning star), with a somewhat less bright companion clearly visible.  NASA has helpfully magnified that part of the image here, but human eyes would definitely see at least Earth and probably the Moon.  But they would be mere points of light, seen here from the world we could most easily one day colonize — but which we likely will not be able to for a long while yet.

Still we must recede, in pursuit of a better perspective.

Earth and Moon, taken by the Cassini spacecraft in orbit around Mars, taking advantage of a photo session from within Saturn's shadow to permit photography of a planet so close to the Sun. (From the outer solar system, all the inner planets are dangerous close to the Sun for photography.) Saturn was 898 million miles away.

Earth and Moon, taken by the Cassini spacecraft in orbit around Saturn, taking advantage of a photo session from within Saturn’s shadow to permit photography of a planet so close to the Sun. (From the outer solar system, all the inner planets are dangerous close to the Sun for photography.) Saturn was 898 million miles away.

With the magnification available in Cassini’s best camera, this is all that can be achieved at this distance.  Earth barely shows enough to confirm it is a sphere, and a bluish one at that (in contrast to its brownish companion). Still, I suppose you could stand on your pixel and scream at the people on another, so let us zoom out as far as presently possible.

Earth, greatly enhanced, in a cutout from a much larger single frame from Voyager 1's narrow angle camera and greatly enhanced to reveal the tiny, faint little world. The full frame is so large it includes not just Earth but also the Sun and Venus with lots of room to spare. Voyager 1 was at a distance of approximately 4 billion miles at the time.

Earth, greatly enhanced, in a cutout from a much larger single frame from Voyager 1’s narrow angle camera and greatly enhanced to reveal the tiny, faint little world. The full frame is so large it includes not just Earth but also the Sun and Venus with lots of room to spare. Voyager 1 was at a distance of approximately 4 billion miles at the time.

That’s it.  The Pale Blue Dot.  Here, we are less than a single pixel.  Our entire planet represents a single value in the image file.  All we have, all we are, all we were, possibly all we ever will be if we don’t get our butts off this rock.  It’s all there, so tiny, so alone, so fragile against the all-encompassing darkness.

Maybe it’s time we started trying to preserve what we have, to recognize how important this dot is compared to all the pointless bloodshed.  To live together, rather than dying apart, because honestly, even if you think it’s a good idea to have countries for individual tribes or religions, the truth is none of that matters.  The whole world is all of ours, and we will do much better if we learn to share it.

Of course, I could just let it be said much better by Carl Sagan, who said all this a long time ago:

Note: the image above is a cutout from this image, which itself is only a portion of the full frame.  We are so tiny….
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