From the Earth to space: the night sky in a continuum of the human environment

Image credit: Greg Rakozy/Unsplash
1620 words / 6-minute read

In June 1969, the Cuyahoga River, bisecting Cleveland, Ohio, on its way to Lake Erie, caught fire. The level of flammable material in the river, resulting from dumping of industrial waste into the river and its tributaries, rose to the point where it could ignite. A Time magazine photographer was there to witness the event. The resulting photo spread in the magazine horrified Americans and galvanized the nascent environmental movement in the U.S. A short three years later the Clean Water Act became law and the health of American waterways began improving.

But, as the U.S. National Park Service tells the tale, the fire was not particularly shocking to locals because it was only one of many such instances historically. “The river had burned more than 10 times over the previous century. The first newspaper coverage focused on the damage, not the fact that the river had burned. At the time, people largely saw the river as a part of industrial infrastructure. In that light, a river fire seemed more normal. It is when we view a river as a natural system that a fire seems out of place." The notion that industrial pollution of rivers was an inevitable consequence of modernity and progress was gradually replaced by refusal to accept outcomes like rivers catching fire. Faced with a parallel situation involving light pollution, is a similar reorientation of thinking the best way forward?

(Non-)traditional views of the world

In an earlier post here, we explored environmental law in the United States context particularly, noting how effective it was during the past half century in substantially reducing environmental pollution. We argued that this represented a kind of road map leading toward comprehensive management of a pollutant (artificial light at night) fouling a valuable resource (natural nighttime darkness).

We also previously wrote about Dark Skies and the "Rights Of Nature". The argument in part was that novel legal theories (at least in the West) that confer some legal rights on natural systems may be a way to pursue protection of nighttime darkness. But the idea has yet to gain significant traction. It relies on an assumption that the night sky is a kind of commons owned by no one, in tension with legal guarantees of private property rights.

With University of San Francisco professors Dana Zartner and Aparna Venkatesan, we recently reviewed what's known about this and related subjects. In our paper, we landed on three broad legal approaches to protecting dark night skies. In addition, we considered individual rights and community rights descending from concepts such as the right to a healthy environment and the rights of future generations to inherit from us a planet where humans can continue to live. 

In the end, we concluded, there are "needed cultural shifts in how we think about the impacts of increasing light pollution and what we are losing with decreasing darkness. ...Creative use of newer legal strategies may address this environmental justice issue and support the need to protect darkness." In short, we need to rethink the issue entirely and try new methods because the old ones aren’t working.

At some level the reason why there has been no meaningful breakthrough in advancing legal protections for dark night skies has to do with the way the sky is treated in our culture and in our law, which centers human needs and desires in our interactions with the natural world. The Western legal tradition places humans at the top of a created hierarchy, below which are the elements of the natural environment. In the Christian worldview humans were given dominion over the natural world and laws were created to govern the affairs of people; it's therefore no surprise that law historically favored human priorities over environmental protection.

A shifting legal landscape

But that began to change during the 20th century. Environmental law began to emerge after a seismic shift took place in thinking about how humans interact with the environment. Although humans have modified the environment for millennia, the scale of that modification tended to be local. Only recently has technology developed to the point that the effects were large-scale or even global. 

Industrialization began to yield environmental harms as early as the 18th century. This accelerated in the postwar years and by the late 1950s environmental destruction itself was industrialized. Science gradually showed how humans were modifying the natural environment in global and ultimately negative ways.

Environmental law was a reaction to the changes that became increasingly evident during the last century. But those laws mainly functioned only at the national level, even if most countries began adopting a canon of similar laws. Environmental pollution respects no political boundaries, so approaches that focus on single jurisdictions are usually inadequate to solve significant problems that result. 

Few international efforts have achieved success, although those that have suggested ways forward: witness the wild success of the Montreal Protocol (1987) that ended industrial fluorocarbon production in order to heal the ozone hole over Antarctica. While limited in scope, Montreal proved that major environmental goals could be achieved if the world committed itself to them. 

A turning point of swords was the recognition that human activity is inseparable from the environment. The U.S. National Environmental Policy Act of 1969 (NEPA) was one of the first laws to introduce the use of the term "human environment". NEPA defined this term "comprehensively" as "the natural and physical environment and the relationship of present and future generations with that environment." It flows from the the NEPA statement of legislative intent, which reads in part "to declare a national policy which will encourage productive and enjoyable harmony between man and his environment; to promote efforts which will prevent or eliminate damage to the environment and biosphere and stimulate the health and welfare of man; [and] to enrich the understanding of the ecological systems and natural resources important to the Nation."

Three years later the UN held its first global environmental conference, the "United Nations Conference on the Human Environment", resulting in the Stockholm Declaration (also here) that led to the establishment of the United Nations Environment Programme (UNEP). This began an ongoing dialogue among nations exploring links between economic growth, environmental pollution, and the well-being of humanity. It also started the process by which the world began reacting to the threat of global climate change.

The human environment is a coupled system: humans impact the environment, and the environment impacts humans. For most of the existence of our species, it was a largely closed system bounded by the atmosphere. If the atmosphere is used as a defining boundary, then even before space travel the human environment extended to the Moon. To the extent that such discoveries come as a surprise, it’s because they challenge our preconceived ideas about how the world is composed and structured.

Space travel changed that by establishing a human presence in outer space, even if only in the form of the artifacts produced by human hands. In the decades, since the launch of the first artificial satellite, orbital space has become an increasingly congested volume around our planet. In many respects, the condition of low-Earth orbit (LEO) is fully determined by human activities there.

New threats, new thinking

In 2023 we wrote here about the effect of satellites on the appearance of the night sky, asking whether the rapid proliferation of satellites in LEO was worth worrying about. The answer at the time was that we didn't really know, given uncertainties about the future development of space. There are some encouraging signs involving voluntary actions taken by commercial space companies, but there are still considerable hazards presented by effects such as the so-called "Kessler Syndrome" of runaway space debris generation. The prospect of space warfare also looms on the horizon, most recently brought into focus by the November 2021 test of a destructive anti-satellite weapon by the Russian Federation. In short, space is an increasingly dangerous place.

Now we're also worried about a potential feedback cycle between the space and terrestrial environments from the spacecraft life cycle. That is to say, the entire process of building, launching, operating, and ultimately de-orbiting spacecraft has its own environmental footprint. A warming climate plus water vapor and black carbon soot emitted into low- to mid-altitudes could increase the prevalence of clouds. Rocket launches are punching "holes" in the ionosphere. Metals deposited in the upper atmosphere during spacecraft re-entry have unknown effects on the Earth's energy budget. All of this probably impacts the visibility of the night sky and comes on top of an alarming increase in terrestrial skyglow in recent years.

Yet existing legal mechanisms, continue to treat the earth and space like they were fundamentally different and decoupled environments unto themselves. That view is increasingly untenable in a world where the connection between those two spaces is demonstrably stronger than ever. Between them is the sky that represents humanity's portal to the stars, views of which inspired untold generations of people to reach for them. As threats to those views now come from both above and below, the need to change how we think of Earth, sky and space as elements of a single human environment is more important than ever.

If humans were to reach the conclusion that the night sky is “environment”, we might begin to treat it differently as a matter of law. That view finds synergy with the related contention that the night sky is “culture” unique to no particular society. In coming to these realizations, we might further decide that there is value in this resource that is diminished by its pollution. For now, we haven’t yet decided that a clean river is what we want — much less acknowledged that the polluted river we already have is on fire.