Behind the Black


At the end of the last spacewalk during this last servicing mission to Hubble, astronaut John Grunsfeld took a few moments to reflect on Hubble’s importance. This was Grunsfeld’s third spaceflight and eighth spacewalk to Hubble, and no one had been more passionate or dedicated in his effort to get all of Hubble’s repairs and upgrades completed.

“As Arthur C. Clarke says,” Grunsfeld said, “the only way of finding the limits of the possible is by going beyond them into the impossible.”

For most of human history, the range of each person’s experience was of a distant and unreachable horizon. This untouchable horizon defined “the limits of the possible.” No matter how far an individual traveled, there was always a forever receding horizon line of unknown territory tantalizingly out of reach before him.

In earliest prehistoric times, the size of the known territory within that horizon line was quite small. Each villager knew a region ranging from ten to fifty miles in radius. He or she knew there were people and villages beyond the horizon, but never saw them. Moreover, even the most traveled explorer had a limit to his range, and knew that at some distant point what lay beyond that horizon was a complete mystery.

Later, as human civilization progressed, the size of known territory within that horizon line expanded. Different cultures met, exchanged information about each other, and recorded the data so that even those who did not travel far from their homes could know something of distant lands beyond their personal horizon. Still, explorers who pushed the horizon found that it continued to forever recede. No matter how far they traveled, the horizon was always ahead of them, an impossible goal beckoning them onward to find new lands unexplored.

Then humans reached the ocean and the sailors took over. To the mariner, there was still a forever receding horizon of great mystery, but he initially feared traveling out towards it because it was dangerous and risky. The ocean was a vast desert, with no food or water. Worse, that desert could suddenly become violent, heaving his ship about and tearing it to shreds.

With time, ship designs improved, and the mariners began journeying outward. The Vikings sailed out into the northern seas to find more lands and more endless unknown territories. Later, using better ships that were more reliable, Columbus pushed the western horizon and this time the visit was permanent. Even for Columbus, however, the horizon was still an impossible goal out of reach. He had sailed west, hoping to reach China and thus circumscribe the very limits of the horizon. Instead he discovered the New World, with its vast new territories and unlimited possibilities.

Nonetheless, the impossibility of touching that horizon had never been a deterrence, for either Columbus or anyone else. As the poet Robert Browning wrote, “Ah, but a man’s reach should exceed his grasp,/Or what’s a heaven for?” People from all cultures felt compelled to reach for that unreachable distant goal, “to go beyond the possible and try to touch the impossible.”

It was with Magellan, however, that the impossible became possible, and the limits of the horizon were finally reached. For though he set out “to sail beyond the sunset,” traveling west as far as he could go, the horizon did not recede forever away from him into unknown lands. Instead, the survivors of Magellan’s epic voyage circled the globe and found themselves back where they had started, in a known place. The unknown horizon was gone. Humanity for the first time knew the limits of the world. The impossible no longer existed.

For the next five centuries the human race was consumed with learning and exploring and settling the limits of this Earth, delving into its every corner, from the freezing poles to the bottom of the ocean to the highest mountaintop. In all cases, however, the Earth was a prison, placing a curb to exploration. No matter how deeply humans probed, they were still trapped on a spherical world, a giant prison floating in the blackness of space. There was no visible but untouchable horizon to reach for.

The Hubble Space Telescope, along with all the early manned and unmanned space probes of the past half century, have given us that horizon back. We are no longer trapped on this Earth. We now can travel outward with increasing sophistication, either in manned spaceships or with unmanned robots like Hubble, pushing against a new infinite horizon that — instead of a horizon line — is a black sky above us and receding away from us in all directions.

Perhaps the best and most noble of all human behaviors has been the never-ending effort to push back against that infinite blackness, to find out what lies behind it and get some fundamental answers to our questions about life, the universe, and existence itself. For me, it is essential that all of us always ask that next question, always challenge what is known so as to find out what is unknown, and always reach out for that “unreachable star.”

Grunsfeld finished his last spacewalk to Hubble by adding this one small thought, “As Drew [Feustel] and I go into the airlock, I want to wish Hubble its own set of adventures, and with the new set of instruments we’ve installed, that it may unlock further mysteries of the universe.”

Hubble, as well as all human exploration, has given us the first detailed and clear glimpse of what lies hidden in the black untouchable horizon above us. May we not shirk from that adventure, but reach out to grasp it fully, even if we cannot ever really touch its limits.

Revised from the afterword of the paperback edition of The Universe in a Mirror.



  • Stretch

    Wonderful Bob. Just wonderfully expansive as the frontier above the sky… Thank you for reaching beyond all of us ;)

  • Greg

    I see that you have studied out the pioneering models of the past, and have a passionate vision of our progress off world. Someday we will escape our present boundaries, no doubt, but before that time, which is yet distant, we must learn to live where we are. Over the years dreamers have all sought perfection in new societies, experimenting with social structures and forms of government, most have failed, many miserably. Paradise is a lost dream on our generation. So we must make the best of what is left, and by doing so, prepare to move off world, not just through technology, but through the experience of making rational adjustments to our social habits and expectations. These activities are not mutually exclusive, and should be pursued in tandem.

    I need you, Robert, as a good communicator, to grasp and advocate this:


    Star architecture communities are a new concept that can radically change civilization. In an age of hyperbole, we tend to dismiss the possibility that such can happen, yet this template can change land usage, politics, transportation, energy needs, carbon displacement, life styles and quality of life for those participating. It would be environmentally friendly. It will affect all local, regional, global politics and markets when applied. They will redefine counties, states, and nations. It will alter the balance of life on our planet while improving all aspects of human interaction and involvement. It provides modulation while allowing room to customize and fineness that provide specialization and characterization. By greatly reducing the need of roads and human land usage, it would open larger corridors for wilderness and animal habitation, design constraints that should always be considered. Those that live within the communities have bought into this and are free accordingly, constrained only by the Charter which will include building and zoning codes. A Master Charter would address the boundary zones of no growth, the distance between Star communities and formations from each other. Collections of Star communities would then form States, Nations, redefining the world politically.

    Star Communities are pre-planned, prebuilt cities organized in star formations, or in other words, each city is interconnected with several other cities that define them as a star or group. Each city is independent in its character and resources and whatever surpluses are generated by one city would be marketed to the others in its group first, then, any surplus left from the group may be marketed outside the group, to other groups or the world at large. Each city will have many attributes, but perhaps abound in one in particular, such as energy production, farming, ranching, fishing, mining, forestry or manufacturing. One city, usually the largest, is designated as the central governing body for that Star formation. Each city would be restricted in its physical size to avoid sprawl and environmental intrusion. Intensive farming and forestry would be utilized, while parks and open areas would be incorporated from the inside area outward to break up the heat signature characterized by modern cities. With storied construction and earth covered facilities, much can be done in smaller areas. Schools could have forest growing over them, with solar tubes passing light into the space blow. Farms could be in multi-story buildings for some crops, with other, wider spaced crops perhaps growing over a dairy that provides nutrients pumped from below. Gases could be collected from the underground roof and utilized for the energy cycle of the production. Range lands could also incorporate herds of cattle or other domesticated animals while harvesting solar power. Managed forest and groves would also be included to the benefit of its owners and so forth, allowing a good blend of land use. If imagined, engineered and cost allow, many possibilities impractical before, can now be realized. Each city in the group would interconnect with it’s hub city with high speed transport, which would have links to other hubs. Airports would also be located within the hub cities and this would be a rational, managed arrangement, limiting the need for air travel.

    Sizes: Mega cities are over built, over populated centers that tend to overwhelm and at times, dehumanize its population who become lost in a sea of strangers. Mega cities are obsolete in the Star community template. Small communities are charming but limited in human resources that are needed to fulfill basic social and economic needs. Some consume as much land area as that of a large metropolitan area, with little useful effect. Star communities will vary their populations from 100 thousand to not more than 250 thousand per city, the larger usually being the central governing body and transportation hub of the Star. The mission of each Star community will be determined in advance by those intending to incorporate it, but each must conform to the overall Charter that will define the Star. Each Star would incorporate a million +/– a few hundred thousand people. Population would be determined by the character of the Star and the resources available to it. Star communities would replace the outdated cities of the world, through attrition and over time. These can be private ventures but would benefit from land grants from the Federal Government, which is the largest land owner in the United States, especially in the Western States. This plan would eventually revolutionize these same States and political adjustments would have to follow. Caution would be needed to keep outdated governments from usurping this effort, or failing that, efforts must be made to work with them to preserve the freedoms required to make this work and every adjustment used to free these fledgling States from tyranny intended or not.

    Each city incorporates according to Charter and will have included in every home, office, or occupied facility the basics that will include power, water, waste management and high speed data utilities, with immediate access to inter city transportation. Each city will have a direct line of transportation for passengers and goods to the center city, which acts as a transportation hub which is also linked to other hubs of other Star communities. Such things as magnetic or mechanically enabled capsules could be used in each home or business to transport package canisters to accommodate small deliveries such as mail and groceries, or in specially tagged canisters, garbage disposal. Exact sizes and payloads of such a drop tube system remain to be engineered, but this sort of thing, if part of the design of the city, would drastically reduce cost and need of transportation and have significant savings of time and resources. By designing the attributes before construction, the possibilities become affordable and exciting. City developers will, over time, be able to select from menu items that will include with each item, demonstrated cost and maintenance figures to assist in determining the desirability of such features. As the engineering and implementation gains in experience, such costs should be easier to be realized without undue economic strain. The hardest part of this program is getting it started. The third Star would begin to realize enormous benefits from the pioneering first and second Star communities. Innovations would become realized all along. Eventually, the first Star communities would be recycled and rebuilt with all of the improvements denied it due to uncertainties or unknowns. This would be a multiple generational cycle. Star communities would, by their Charter, build into them twenty to twenty five percent surpluses to help absorb displaced communities evacuated due to disaster or maintenance, each Star capable of sustaining a displaced City within its system. Such redundancy should be standard.

    Robert, that’s the idea in a thumbnail sketch. It needs some help to carry it forward. Such an undertaking would require the expertise of every trade, every science. It requires a new set of pioneers to set it into motion, into reality. When we learn to live here and properly use our present resources, off world colonization will become more feasible and our experience will allow it to happen.

  • Arguing on the Internet is like running in the Special Olympics: Even if you win you’re still retarded.

  • Scott


    Tsk, tsk… I see you’ve been reading Thomas More again – or maybe you came across a copy of Lost Horizon. Either way, Greg, I would caution against this line of thought, as it has been known to lead some men down the authoritarian trail. (if you know what I mean)

    Now, I’m not a religious man, but I do take note of wisdom wherever I find it lurking:


    I wonder – was Eden merely an early form of “Star Community”? Oh, well…Guess it doesn’t really matter. Didn’t work out quite the way the maker intended. Or, maybe you’re proposing something more along the lines of the early English poets: “…the houses were made of barley sugar and cakes, the streets were paved with pastry, and the shops supplied goods for nothing.”

  • gayle

    Is it possible that the reason we have not found any radio signals from outer space, is that more advanced civilizations may very likely consider this “space garbage” and clean it all up? My comment comes from your statement on Coast to Coast that we have a 60 year “band” of TV signals all around our solar system.
    thank you for your wonderful additions to Coast to Coast.

    • Anything is possible. I think it more likely that, as I said on the show last night, that the ordinary advance in technology produces methods of communication that don’t require broadcast signals. Instead, communications are transmitted by cable, fiber optics, and even laser communications (as I reported today), all of which do not produce any signal that can be picked up by accident by others.

  • Larry DM

    I always look forward to your guest appearances on the John Brothers show. I find your enthusiasm for space exploration to be of a contagious nature. Thank you for sharing with us.

    • Thank you for the kind words. Note that I think you had a brain shut down in writing your comment, as I think you meant to say the John Batchelor Show, not John Brothers. However, I’d love to go on John Brothers’ show, if you let me know where and when and who to contact! :)

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