Behind God's Door
The Hubble Deep Field
Author’s note: this is the second post from a series of essays on some of my favorite astronomy images. You can find the first post here. Today: the original Hubble Deep Field from the Hubble Space Telescope.
I don’t think I would have been that bold. After all, it’s the Creator you’re testing, the mind of God you’re trying to probe. Not to mention: public relations on thin ice, a giant backlog of deserving projects already delayed, and decent odds you wouldn’t see much. A waste of precious telescope time. Any normal committee would never approve. We point telescopes at objects, not at nothing.
Yet good thing Bob Williams thought otherwise. Good thing Bob Williams had the nerve to face his Creator. In the end, I’m not sure there’s been one single image that has told us more about the history of our universe than this one. Not one single image that has given us such richness, such variety and uniqueness. Such a sense of place in the universe we live in.
Though I was only six years old when the data came down in December of 1995, here’s what I’ve been told of the story of a picture that continues to impact astronomy in my adult years.
First you have to go back to the spring of 1990, when astronomers were analyzing the first images from the Hubble Space Telescope (HST). HST was the product of decades of development, strife, delays, and over $1.5 billion; one historian at the time called it not just the most expensive telescope ever built, but the most expensive scientific instrument ever built. NASA was still recovering from the Challenger shuttle disaster: its future in question, its hopes focused on this large space telescope. Would it be worth the cost?
Most clearly thought so. “If we are disappointed, it’s not the telescope’s fault or our fault,” astrophysicist John Bahcall told the New York Times magazine around the time of the launch. “It will be because of a lack of imagination on the part of God.” Here it was: humanity’s most audacious attempt to peer into the the mind of God since Babel. The telescope launched, opened, data started coming down.
And then, disaster. Something clearly wasn’t right. What should have been the sharpest images in history had a distinct fuzziness, donut rings from a misshapen mirror. An engineering mistake, and Hubble could barely see. “Can the U.S. Get Things Right Anymore?” asked The Washington Post. “NASA’s $1.5 Billion Blunder” declared Newsweek’s cover.
For over three years NASA engineers, scientists, and astronauts worked furiously to find and implement a fix to the problem for the poor deformed telescope, floating alone up in space. For over three years they worked on new corrective lenses, new glasses to correct its sight. The press was ready to pounce. “If the Hubble repair is a failure, we can write off space science for the foreseeable future,” worried Dr. Bahcall. To make room, an entire scientific instrument had to be jettisoned. To make ready, astronaut Story Musgrave suffered frostbite on 8 fingers while testing installation tools. There were so many things to fix. Finally, in December 1993, astronauts conducted over 35 hours of spacewalks spread over 5 days, in what NASA called “one of most challenging and complex manned missions ever attempted.” And when it was over, Hubble’s astigmatism was gone. The HST could see again.
The new images were everything people hoped for. But telescope time was at a premium. Everyone had things they’d wanted to look at for years and years, burning questions to answer. You felt a ticking clock before something else went wrong.
Astronomers would submit carefully crafted proposals for how to use the telescope, which would be intensely scrutinized by committees of experts: less than 15% of the requests would be granted. There were too many good ideas, and not enough time. The committees, reasonably, tended to prioritize shorter, high impact projects: spreading around the time, and focusing on clear outcomes. Especially given all the bad media up to this point, it was important to have clear, distinctive wins.
Enter telescope director Dr. Robert (Bob) Williams, and his crazy idea. Dr. Williams was responsible for 10% of the telescope’s time for non-committee reviewed observing — he could do whatever he wanted. And here’s what he wanted, to the chagrin of many astronomers at the time: to take the most expensive telescope in history and have it just stare at this one blank spot of sky, orbit after orbit for 10 days. Nevermind that there’s an impossibly long queue of interesting objects that astronomers want to look at. Never mind that a peer review process would never grant such a crazy plan. Why spend so much time to be disappointed by God? But it was his time to burn. “If it’s that bad, I’ll resign,” Dr. Williams said. “I’ll fall on my sword.”
With a team of young, rash astronomers Williams identified a tiny patch of sky near the Big Dipper — no bigger than a tennis ball viewed from across a football field — which contained no known galaxies, and essentially no known stars. Viewed with a normal telescope there was nothing there. Viewed with Hubble - no one knew. So they looked. For 10 days.
And as the scriptures say, “seek, and you will find.” As it turns out, the limitations were in our imaginations, not God’s. The universe responded beyond their wildest dreams. Look at this picture. Of the over 3000 objects detected, only 20 are stars in our own Milky Way. Everything else is a galaxy, like our Milky Way, containing billions of stars. But what variety, what a tapestry of color, shape, and size. Like getting a snapshot of the whole human population, nay, the whole animal kingdom, in one frame. Butterfly to giraffe. Tadpole to elephant. All at once.
I remember once visiting a museum that had an exhibit about the woods. The exhibit contained an illustration that at first just appeared to be trees. But the longer you looked, the more animals you found. Not just different animals, but animals at all their life stages: baby fawns, teenage does, aged bucks. You could learn about the full life of a deer, from birth to loosing its spots to antlers to death all in one deep detailed look at these woods. So too, with the Hubble Deep Field. Infant irregulars, mature spirals and aged, domineering ellipticals all here in this one deep look.
And there’s more. Some of these objects are closer to us – if you can call a few billion light years close. And some are much much further. The most distant galaxies ever detected at that time – and some of the most distant still – are in this picture. Tiny red dots containing billions of brilliantly burning suns, hot, bold, and also young – ready to take on the universe. We know they are young because there’s another amazing thing here. This image is a time machine. Because it takes light time to travel here, we’re seeing the galaxies as they were when the light left them: light that left a galaxy a billion light years away is just getting to our eyes now, so we’re seeing it like it was a billion years ago. Or 5 billion. Or 13 billion - the most distant baby galaxies, seen just after the birth of our universe. The image is a look back to the beginning, the time of galaxy creation, a time when God said, let there be light.
A tree is a magnificent being, a being that contains within it a full record of its history. A narrow probe cut into its trunk reveals in its rings the droughts, famine, and abundance of each year of its history. In one tiny slice, the story of its life. So too with the universe, a creation of similar magnificence. With this HST picture we’ve probed the story of the universe, taken a coring on which we might count its rings. “Time,” Richard Powers writes, “is one spreading ring wrapped around another, outward and outward until the thinnest skin of Now depends for its being on the enormous mass of everything that has already died.” In this image we peer back at that inner history, not dead, but alive, shimmering, a canvas masterpiece of where we come from.
All this from that tiny sliver of apparent darkness. I’m glad we looked. Knock, and the door will be opened: behind it, you never know what you might find.
References and Further Reading:
NASA.gov; NASA Servicing Mission 1 (accessed 1/19/2024)
Drake, Nadia. When Hubble Stared at Nothing for 100 Hours. National Geographic, 2015.