‘Space Photography’: The art of scientists transforming pixels into pigments of the imagination

We went out to Caltech the other evening for the opening of “25 Years of Space Photography” in Baxter Art Gallery; I’m not sure how much of it is science and how much is art--but the results are beautiful.

The exhibition is of photographs taken by the Jet Propulsion Laboratory’s unmanned spacecraft in 25 years of exploring the moon and the planets for NASA.

Of course the technique involved is not as simple as when our Aunt Effie goes to Egypt with her Instamatic and comes back with pictures of the pyramids.

But the reasons the pictures were taken were pretty much the same for Aunt Effie as they were for JPL’s scientists, who are, after all, only little boys who grew up with lots of curiosity.

Says JPL’s Dr. Albert R. Hibbs in the exhibition’s brochure: “For the scientists, as for the general public, the first question was, ‘What do they really look like?’ ”

One of the first things we found out was that the moon is not rugged and boulder-strewn, and marred by flows of lava, as we had imagined, but fairly smooth and rolling, like a desert, and safe enough for men to walk on.

On the other hand, close-ups of Mars make that planet, on which we have so often fantasized a neighboring civilization, look indescribably wild, rough, bleak and unlivable, with great boulder-strewn dunes, massive dust storms, carbon dioxide clouds, a canyon three miles deep and as long as the distance from San Francisco to New York, and Olympus Mons--435 miles at the base and 80,000 feet high, the largest known volcano in the solar system.

One views these awesome landscapes with a dwindling belief in “The Martian Chronicles.” Ray Bradbury must have made it up, for surely such charming people could not have lived on such a planet. Nor, as far as we can see, can anything else.

One of the loveliest images is of Jupiter’s moon Europa, from Voyager 2. It looks smooth, unscarred, a pale bright orange.

“It’s flat,” Hibbs says of Europa. “Absolutely smooth. I shouldn’t say it’s flat because it’s round; but smoother than the smoothest possible ball bearing. Everything else is all covered with craters, but not Europa. It’s a smooth ball of ice, which implies that underneath the ice is liquid water. . . .”

Among the most striking images is one taken by Voyager as it sped away from the planet Saturn. The right half of the sphere is sun-bright and the left half is in blackness, a solid shadow that falls across the planet’s beautifully delineated gilded rings. It is a picture that we might very well hang on our walls and not disgrace a Rembrandt (if we can imagine having a Rembrandt).

When we go outdoors on a clear night and look at the sky, we imagine that we are a part of an all-enveloping, spherical universe; but a picture of nearly the entire heavens, taken by a mission called IRAS, shows our galaxy as a narrow horizontal band, burning bright, like a Fourth of July fuse.

I have an idea that our art critics will be taking a look at this exhibit, and I won’t try to anticipate their perceptions. But it will be interesting to see whether they decide this is art or science, and if it is both, then who was the artist? And what was his concept? And how does this work compare with modern abstract art?

No picture is done by any one man. The little machine is flying through space, and when it nears its target planet, an electronic message from JPL tells it to take a picture. The picture is taken by a telephoto lens and is divided electronically into rows of small dots of picture elements called pixels. One row of such dots will go across the top of the picture, and several hundred rows will go down its length. A readout system scans these spots and measures how much light fell on each one as the picture was taken. This measure is expressed in numbers from zero to 255. These numbers, several hundred thousand for each picture, are transmitted back to Earth, where a computer directs a thin laser beam to reproduce each dot on a piece of photographic color film.

Because the scientists on Earth can control the computer and the lasers, they can control the colors of the pictures they produce. Sometimes they choose the colors quite arbitrarily, to see how a certain landscape looks in blue, perhaps. Usually they do it for scientific reasons; to obtain more contrast, to illuminate more detail. But the results sometimes, whatever their reason, are spectacularly beautiful.

Thus, one of the photographs shows Saturn as a ball of lovely laminated pastel layers, wearing, as always, its rings.

It was “imaged” in false colors, we are told, to increase the visibility of features in the north temperate belt; and it was taken through ultraviolet, green and violet filters.

It will be hard to think of Saturn ever again without thinking of it as looking like that.

In a philosophical essay on the exhibition, Christopher Knight observes that while the space photographs are beautiful, “it is the terror, obscurity, difficulty and vastness of space itself that is sublime.”

What gives this photograph its “freakish and incomparable quality of strangeness,” he says of another photograph of Saturn, is dauntingly simple. “This photograph repeats to me incessantly that I will never see Saturn and its famous rings. “

Oh well, most of us will never see heaven, either.