The Night Sky: An Endangered Species

“The heavens declare the glory of God, and the firmament proclaims his handiwork.”  –Psalm 19:2

“Lead me on kindly Light of Truth, amid the encircling gloom…”  --Saint John Henry Newman, 1833

“Today we can illuminate our cities so brightly that the stars of the sky are no longer visible. Is this not an image of the problems caused by our version of enlightenment? With regard to material things, our knowledge and our technical accomplishments are legion, but what reaches beyond, the things of God and the question of good, we can no longer identify.”   --Benedict XVI, April 8, 2012

The famous nineteenth-century poem, “The Pillar of the Cloud,” better known by its hymn title, “Lead, Kindly Light,” was authored by a brilliant and influential young Anglican priest-scholar during a twofold physical and spiritual journey. Father John Henry Newman, who was sailing northwestward across the Mediterranean Sea from Italy to France in June of 1833, had also embarked on an earnest quest for the fullness of Christian truth. When his orange boat was becalmed for a week in the Strait of Bonifacio, he penned these simple, evocative lines, humbly beseeching the gentle light of divine truth to guide him one step at a time through the darkness of doubt, uncertainty, and error. God heard and answered Newman’s prayer, leading him gradually to the fullness of divinely revealed truth in the Catholic Church.

Christianity and Catholicism teach that God created “the heavens and the earth” (Genesis 1:1) out of nothing, ex nihilo, and entrusted to humanity, his masterpiece, the responsibility to develop and care for his creation. The importance of protecting nature was frequently stressed by Pope Benedict XVI, who installed solar panels on the roof of the Paul VI Hall in 2008, and it has been a dominant theme of Pope Francis’ pontificate, discussed in detail in his groundbreaking 2015 encyclical Laudato Si’ (Praise Be to You). For sincere Christians and Catholics, faith in the Creator of nature and good stewardship of the natural environment go hand in hand, and care for creation is both an individual and a communal responsibility.

In his important 2009 encyclical Caritas in Veritate (Charity in Truth), Benedict XVI, echoing his predecessors, heartily affirmed the basic goodness of the scientific progress and technological advancements that have marked the Industrial and Digital Ages. At the same time, in continuity with recent papal thinking, Benedict soberly observed that scientific and technological development detached from fundamental religious and moral values inevitably has destructive consequences for humanity and the natural environment. In Laudato Si’, Pope Francis rightly criticizes the many forms of environmental degradation and pollution with which unscrupulous human beings have flooded the earth since the dawn of the Industrial Age, driven by a lust for profit that trumped concern for our common home.

One form of environmental contamination not mentioned in either encyclical (or, to this author’s knowledge, in any official Church document, for that matter) and generally overlooked today is light pollution. Since the invention of the long-lasting incandescent light bulb by American inventor Thomas Edison in 1878, electric lighting has become a ubiquitous and essential hallmark of modern civilization throughout the developed world and has become increasingly widespread in developing countries. During the past century and a half, the marvels of incandescent, fluorescent, and LED lighting have replaced candles, kerosene lamps, and gaslights as our primary light sources, making all aspects of human life and activity much easier and safer, especially during the nighttime hours.

Unfortunately, in recent decades, especially in North America, Europe, and Asia, the steady growth of artificial illumination at night has gradually deprived the great majority of Earth’s population of a sight our ancient forebears took for granted: the starry sky on a clear, moonless night. Our naked-eye view of the majestic heavens, unprecedentedly enhanced by sophisticated telescopes and cameras, is now increasingly threatened by our excessive and irresponsible use of electric lighting, particularly in urban and suburban areas.

Satellite cameras continuously monitoring our planet since the 1960s have candidly documented the rising number and intensity of artificial light sources across populated areas of the continents at night. Conversely, these satellites have revealed that locations across the globe that enjoy truly dark nighttime skies have been constantly shrinking and vanishing. Worse yet, more recent satellite photographs indicate that this phenomenon of ever-increasing light pollution has accelerated dramatically since 2010--even as human population growth in developed countries has been slackening during this time because of the culture of death—due to the rapid spread and largely unregulated use of outdoor LED illumination.

In his infinite goodness and perfect wisdom, our loving Creator designed Earth’s atmosphere to be transparent to visible light, allowing us to explore from our home planet the vast and beautiful cosmos that he fashioned to surround it. In a truly dark rural location on a clear summer or winter night when the Moon is absent or less than half illuminated, the gentle glow of a star-spangled sky bisected by the delicate white ribbon of the Milky Way Galaxy is a marvelous sight to behold. The light from most of the 3,000 individual stars sprinkled across the firmament has taken anywhere from dozens to hundreds of years to reach our eyes because of their great distances from us; yet these are only our nearest neighbors in space. The Milky Way itself is visible to the unaided eye thanks to the combined light of many billions of stars so much further distant that they appear to form solid masses despite most of them being light-years apart from each other. Binoculars, telescopes, and megapixel CCD cameras allow us to penetrate much deeper into the universe and further back in time to see many more stars, as well as nebulae and other galaxies, as they appeared long ago.

The great medieval philosopher and theologian Saint Thomas Aquinas wrote that human beings come to know about God through their senses. By seeing, hearing, touching, smelling, and tasting the amazing variety of good things God has created, we can learn something about the nature of their Creator. The intricate design, sheer diversity, and mutual interdependence of plant and animal life on Earth’s surface and in the rivers and oceans reveals to us God’s intelligence, wisdom and providence. While Scripture tells us that all aspects of creation manifest the glory of God, it says so most specifically of the heavens. And while a person can conceivably come to know God by seeing only what he has created on this Earth as well as the Sun and Moon, for so many of our contemporaries to go through their entire lives without ever witnessing the gentle light of the Creator’s celestial handiwork in a dark sky with their own eyes is a terrible impoverishment!

In far too many places in our country and the world today, more electric lighting is used than is necessary for the purposes it serves, and it is installed and utilized without any consideration for the cumulative side effects of artificial light emissions on humanity and the natural environment. This is especially true of the harsh and unfriendly LED lighting that has gradually invaded every nook and cranny of our nighttime lives from streetlights and car headlights to flashlights and solar lights within the past ten years, rightly hailed for its cheapness and energy efficiency. Apart from its aesthetic offensiveness to which we have been dulled by constant exposure and increasing evidence of its negative effects on human health, the major problem with this currently dominant form of artificial illumination is that most of it radiates strongly in the blue portion of the visible light spectrum. As professional and amateur astronomers are painfully aware, blue light scatters very easily throughout the atmosphere, rendering it the primary cause of the global light pollution disaster we now face. With the inexorable spread of “white” (i.e., blue-emitting) LED brilliance into rural areas, even the last remaining bastions of dark sky country are now at risk of being lost.

Regrettably, there is so little knowledge and awareness, let alone discussion and debate, among the general public on the issue of light pollution that it is not even on the radar screen of most local, state, and national policymakers. Until citizens are sufficiently informed and motivated to insist on legal protections for the vanishing treasure of the starry heavens, there will be no reason for our elected representatives at any level of government to enact direly needed artificial lighting emission regulations or to provide incentives for the general manufacture and installation of environmentally friendly lighting.

The principle of subsidiarity, a core tenet of Catholic social teaching, indicates that wherever possible, change for the better should begin at the grassroots level, one person at a time. Regardless of whether we live in an urban, suburban, or rural location, our individual choices and examples can contribute to either exacerbating or eradicating the modern plague of light pollution.

I live in the mountains of western Virginia where nighttime skies are still some of the darkest in the eastern half of the continental United States. Even here, however, within the past several years there has been a perceptible increase in artificial skyglow on the southern horizon caused mainly by gradual LED infiltration in the nearby small town. As a longtime amateur astronomer who has been concerned about this issue for many years, I decided to take a few simple measures to make my own home more dark-sky friendly.

The biggest offender on my premises was a heart-shaped rosary light on the east-facing wall of the house almost entirely made up of bright blue LEDs (the worst kind), which threw a lot of stray light into the eastern front yard and the sky above even with a substantial porch roof overhang. Rather than turn it off altogether, I tried applying an inch or two of masking tape to each of the 53 blue light bulbs. This dramatically cut the blue light emission into the yard while allowing the harmless red and nearly harmless orange bulbs to show up better, and the whole rosary light pattern is still clearly visible from half a mile away. This is a win-win situation as I can witness my Catholic faith and protect creation at the same time.

Another significant source of light pollution was the set of inexpensive solar-powered lights in my yard. A few years ago, I had purchased and installed twenty of these to illuminate the walkway leading from my driveway to the kitchen door. While observing the night sky one evening, I glanced over and was alarmed at the brilliant glow of bluish-white light they were collectively emitting in the western front yard. I quickly reduced their number to ten and subsequently lowered it to just six, which provided adequate illumination with much less light pollution.

Additionally, I have good old-fashioned 60-watt incandescent light bulbs in the two porch lights on the north and west sides of the house. Unlike fluorescents and LEDs, this traditional bulb type radiates mainly in the red portion of the visible light spectrum. Red light does not scatter, so it does not contribute to light pollution. However, incandescent bulbs do also emit quite a bit of yellow light, which scatters somewhat, so I decided not to use any 75 or 100-watt bulbs outside.

Finally, the emergency propane-run electric generator on the west side of the house has a little bright green light on the side to indicate that the unit is functioning properly. Green light is terrible for the night sky because it scatters nearly as much as blue light does, so I cut out a square piece of plastic from a one-gallon water bottle and attached it to the generator with masking tape. The green light is still easily seen at night but without unnecessary radiation into the yard.

The global epidemic of artificial light pollution is getting worse all the time, with fewer and fewer people able to see the star-spangled, Milky Way-strewn night sky as the Creator intended it to be seen, and very little is being done to address this problem. The good news is that, unlike some other forms of environmental contamination, light pollution is entirely reversible. The night sky may be a critically endangered species, but with a bit of common-sense research, planning, ingenuity, and legislation, it can and should be well preserved for current and future generations of humanity. This author makes the following recommendations for the United States:

1) All incorporated cities, metropolitan areas, towns, and counties throughout the nation should enact lighting ordinances to reduce and eliminate sources of excessive and poorly designed outdoor artificial illumination that contribute to light pollution at night. These emission regulations should be tailored to the specific needs of each community; for example, a densely populated urban area with severe light pollution will require far more stringent and detailed laws than a sparsely inhabited rural location that enjoys dark skies. These ordinances should restrict both the types and amount of outdoor artificial lighting installed and employed along public thoroughfares and in commercial, industrial, residential, and rural areas during nighttime hours. They should set target dates for full implementation that allow their communities sufficient time to make the necessary changes in outdoor lighting infrastructure. Finally, they should carry fines for noncompliance.

2) These outdoor lighting emission regulations should be most strict during—or could even only apply to—the fully dark hours of the night between evening and morning astronomical twilight, when the Sun’s light is completely absent from the sky and the faintest and most distant stars and galaxies are visible to the naked eye and through binoculars and telescopes. While astronomical darkness typically begins about two hours after sunset and ends about two hours before sunrise, this varies considerably with latitude and time of year, so lawmakers in each locality will need to consult accurate sunrise/sunset and astronomical darkness timetables to determine what portion of night the ordinance should be in effect during each part of the year. (Due to perpetual twilight, locations north of 50° north latitude, including Alaska, do not experience any astronomical darkness from mid-May through late July.)

3) By state law, the number of flashing blue lights on state police cars at night should be limited to four of 200 lumens each, with no more than two illuminated at any given moment.

4) By federal law, all LED, fluorescent, and other light bulbs and fixtures designed for outdoor use, whether manufactured here or imported from abroad, should be subject to spectral analysis before they reach the market to determine the colors of light they emit. Any bulb or fixture producing more than 500 lumens that radiates primarily in the green, blue and/or violet portions of the visible light spectrum should be banned or limited to indoor use only. This policy would eliminate most factory installed and aftermarket LED headlights in automobiles, semi-trucks, motorcycles, and ATVs, which are now major contributors to light pollution nationwide; it would also proscribe green and blue LED price signs at gas stations and holiday light strings consisting entirely of green, blue, violet, or white LEDs. Finally, this rule would require that green LED traffic and railroad signals either be dimmed slightly at night or replaced with another type of green bulb to reduce glare.

5) Congress and the president should reverse the legislative ban in effect since 2012 on the domestic manufacture of incandescent light bulbs. They should also enact legislation that includes tax incentives to encourage the domestic research and development of artificial outdoor lighting that is both dark-sky friendly and energy efficient.

6) Also by federal law, permanent zones of specially restricted outdoor lighting should include and surround each of our national parks, extending at least ten miles from their borders to protect the darkness of their skies.

The idea is to form an interlocking matrix of local, state, and federal outdoor lighting emission regulations that would effectively halt and reverse the raging pandemic of artificial light pollution. Regardless of whether they live in the inner city, the suburbs, a small town, or the countryside, all Americans who can see should have access to sufficiently dark skies that at least a few hundred stars are always visible on a clear night when the Moon is absent or less than half full.

It is no accident that the recent worldwide jump in visible light pollution has occurred at the same time, in the same places, and in the same proportion as the spiritual light of faith in God has been dimmed and extinguished in modern civilization. Indifference to the Creator and disrespect for his creation go hand in hand. As Benedict XVI wisely points out in the quote at the beginning of this article, the polluted night sky is merely a symptom of our version of enlightenment in which we are so dazzled by our own inventions and accomplishments that we can no longer see beyond them to the great religious and moral truths of our own existence or the origin, destiny, and meaning of the universe itself. The kindly light of divinely revealed truth has a difficult time penetrating the bubble of a radically secularized society and culture determined to navigate by human lights alone.

As believers in the perennial truths that an infinitely good and loving God created the cosmos and that human beings are stewards of creation, Catholics and other Christians should be at the forefront of a mass movement to restore, improve, and protect the visibility of the night sky in the United States and around the world. They should work together with people of goodwill everywhere to ensure that the open book of the Creator’s handiwork in the firmament above can be read by anyone with eyes to see. When that day finally comes, then the “kindly light of Truth” will have a chance to penetrate the darkness of error enshrouding the minds of so many more modern men and women, beckoning them to emerge from their self-constructed cocoons and embark on the fulfilling adventure of faith.

Copyright © 2021 Justin D. Soutar.