Tag Archives: Stars

A Sky Without Stars: Light Pollution & Human Health

Photo by Caleb Woods on Unsplash

The daylight hours stretch and yawn – extending themselves into the blue edges of the night. I awaken to stars and remind myself that soon they will change – my navigable position on this planet under a glittering sky. This intergenerational knowledge passed into my mind as a child is far older than anyone in my family can remember. My grandfather taught my father and they taught me. Should I ever be lost, wait for nightfall and gain orientation by listening to where the night sky tells you to go. This comfort of belonging and knowing my place in the world is the definition of solace. Cities and light pollution strip me of a knowledge so ingrained in my neurological system I can barely explain with verbal language how I know where to go. I become disoriented.

It took my first trip to the antipodes for me to understand this fully, and not for any reason related to light pollution. Instead, when I stared up into the sky, I failed to orient myself with any landmarks. Gasping for breath in the consuming sea of stars, to gain footing I required the Southern Cross. And even with this point established, it was no Polaris, not in the way I knew or expected. Over my time in New Zealand I gained orientation, at one point finding myself in a forest of glow worms with a full dark sky above. As I traveled elsewhere in the South Pacific, the Southern Cross failed as my anchor.

Having watched and photographed galaxy rises, my back against the earth as it hurdles through space, I ponder the impacts of light pollution on those with celestial navigation as a part of their blood, be it land or sea. Before city lights, for hundreds of thousands of years, humans evolved, watching the stars and orienting ourselves alongside their existences, giving their clusters names. We immortalized warriors, kings, ethical dilemmas, and the foundations of our beliefs in Super Novas, Neutron Stars, White Dwarfs and so many other identified and yet to be identified or understood dots of light filtering through our atmosphere from billions of light years away.

And now we can’t see them. Nor can our children. Nor could many of my peers during their formative years. But what impact is this having on our health?

In December, 2020, the Southern Economic Journal published the first ever study on the link between premature births and light pollution. This showed a 12.9% increased likelihood of preterm birth associated being able to only see 0.25 – 0.33 of stars visible under dark sky conditions. Skyglow, as measured by Walker’s Law (the sky-glow intensity from a light source is approximately proportional to the distance raised to the −2.5 power), has a direct impact of fetal health. Premature birth increases the risk of neonatal mortality. Premature birth of a child is closely associated with postpartum depression in mothers.

But this is not the first time researchers have raised concerns about the link between light pollution and impacts to human health. In 2011, the journal Medical Hypotheses published a review article on light pollution’s disruption of circadian rhythm potentially contributing to the rise in obesity. These impaired metabolic processes relate to circadian gene expression conserved through all mammalian species that regulate at least 10% of our genomes, including those of household pets. This article discusses the comparative obesity problems observed in domesticated animals (including horses!) living alongside humans under light pollution conditions. Going into more detail the health impacts of circadian disruption, the article mentions studies on shift work’s impacts on the release of hormones such as insulin independent of lifestyle choices by individuals. Shift work’s negative impacts on health, while linked to light pollution by exclusion of other causes, has additional epidemiological evidence to back it up. Let’s return to that question of gene expression and focus on the metabolic gene clock. Yes. That’s the actual name.

The International Journal of Environmental Research and Public Health published a review Lighting in the Home and Health this month (January 2021). Focusing on the impacts of types of lighting and its impacts on human health they concluded that though not enough studies exist at this time. Their review found suggests insufficient natural lighting increased risks for infectious diseases, injuries, and self-reported depression. While reviewing artificial lighting, they divided the data into multiple categories: fuel based lighting and electric lighting. While fuel based lighting was associated with adverse health from the toxic effects of the burning fuel (asthma, increased risk of respiratory infection, etc) and potential physical injuries, the lighting provided lower self-reported depression with even minimal usage. However, the toxic effects of the burning fuel varied greatly based on the fuel, whereas the increased infection risk remained constant among electric light users. Artificial lights were found to be associated with increased incidence of farsightedness in some children.

The strongest impacts from artificial lighting came from its use after dark, impacting sleep quality and subsequently health. The most notable health impacts from prolonged exposure to artificial light (regardless of lifestyle) at night included primarily metabolic disorders such as obesity, type 2 diabetes, and dyslipidemia in elderly populations. This raises a concern: are these sensitive populations, indicating a more serious underlying issue the rest of society is experiencing?

In the 1950s the Circadian Resonance Hypothesis was proposed by Pittendrigh and Bruce and published in Nature. This stated that an organism’s overall fitness is proportional with the coupling of its internal circadian rhythms to its surrounding environment. While very few studies exist focusing on the impacts of artificial lights and light pollution on human health, many do exist focusing on the negative impacts on the ecosystem, biodiversity, and wildlife. Need I remind everyone reading this, humans do not exist in an isolated vacuum from the ecosystem and are in fact likely experiencing ill effects much like any other mammalian member, though our niches within that ecosystem may vary.

As I consider my future living in another city where light pollution drowns out the stars leading me home, I begin plotting my respite escapes for the sake of my own health. What more can I do until policies change and we find alternative solutions that let us turn down the lights?


Thanks for taking the time to read my writing! If you enjoyed this essay, please take a moment to like, share, and/or comment. It helps others find it and read the scientific articles I’ve linked.

Announcement 20 March, 2020: Rating Scale

Is Haskell is practicing the art of camouflage to avoid rating anything? Nope, that’s just me.

Initially, I *did not* want to give ratings. I wanted to write reviews and post them only here and Twitter. But life is not that way. In order to come up with some way of objectifying my scale I meditated and thought through this process methodically because I refuse to be subjective 100%. I tried to establish a rating scale of 1-5 over the course of September – November 2019. Thank you to all of the indie authors that patiently worked with me as I developed this rating system.

Then that one book by those Best Selling Authors happened that dragged on and *really* shaped the bottom of the rating scale.

I admit my biases because I don’t hide those things. I am accused by some of being too honest. Not in the “you talk too much” way – more like the “you’re too blunt” way. I refuse to do paid reviews, ever, on ethical grounds, but I understand that ethics are subjective. Every person is allowed to shape their own independent understanding of right and wrong. ANYWAYS – I wanted the whole process to be less subjective – I didn’t want to guess on what number I was giving a book. That’s not fair to the author or the reader.

As an aside, I’ve taught nursing students. Nursings students would lose their ever-loving minds if grades were entirely subjective like some book ratings seem to be. Have you met a nursing student or been a nursing student? I think of authors in the same way – intelligent, detail-oriented, hyperaware, and information-seeking. It is not fair for reviews to be entirely subjective, just like it’s not fair to anyone in the position of teaching or taking a microbiology lab for nursing students.

A bit about my rating scale:

5 stars are reserved for books where I absolutely love the story. They must be very close to meeting the 1/10,000 word editorial standard for basic proofreading or blow me away and move me. Any book I am immediately inspired to gift to someone in my life automatically gets a 5/5.

4 stars are reserved for books where I love the story, but they don’t meet the 1/10,000 word editorial standard, have some consistent problems, or have one or two major content concerns, such as a major plot hole.

3 stars are reserved for books where I do genuinely enjoy the core story, but the book does not meet the 1/10,000 word editorial standard, has many consistent problems with following sequence of events, requires a large amount of work on the part of the reader to understand the story, and/or possesses additional concerning issues. My long form review may be vague – I do that as to protect the privacy of the author. As many authors I have previously reviewed books for know, just because I don’t say the page number in the review, doesn’t mean I don’t have it. I can refer you to examples for every single concern I mention.

I do not publicly post 1 or 2 star reviews for any author that is not a “Best Seller”. Even then it may take me 4 months and I’ll need to have a good reason. I will send unposted reviews privately by request to the author only. These are NOT available to anyone else. I won’t add these ratings to GoodReads or Amazon without talking to the author first. Point is: I will still write an honest, thoughtful review with constructive criticism explaining why I had that reaction even if it’s for the author’s eyes only. When I say my reviews are author oriented – this is what I mean.

Things that never influence a the rating a book is given: the additions of content warnings or anything related to the sensitivity of the content. This is too subjective for me to base a rating on. I will mention it in the review for the benefit of potential readers, particularly if there is reason to believe that the content could be potentially harmful. I have never, ever allowed this to impact a book’s rating. If I suggest an author consult with a sensitivity reader, this does not influence the rating of a book and is because I genuinely believe the author would benefit from hearing a professional perspective. I am not a professional sensitivity reader.

Authors are welcome to request examples to be added to reviews for clarification. I can always add detail to reviews and edit them to reflect changes made if an author notifies me of what has changed in future editions.

I am meticulous in detail in my notes and am happy to share examples of the trending issues directly. My notes focus on Fundamental Editorial Standards. FOR EXAMPLE: POINTING OUT THE NEED FOR FACT CHECKING BECAUSE AN AUTHOR’S BOOK SAID THAT NASSAU, BAHAMAS IS IN THE SOUTHERN HEMISPHERE IS NOT “STUPID NITPICKING”.

I research what current readers care about – I spend hours dedicated to ensuring my review benefits both a reader and the author. Please remember that I AM NOT BEING PAID AS A DEVELOPMENTAL EDITOR, so please do not expect me to provide feedback to the extent of one. It is the job of the author to hire a paid developmental editor if their book requires one.

I’m an indie author too, y’all. I put out short stories bi-weekly and I’m working on longer manuscripts. I do this because I’m publishing a book soon and I write short stories. I make mistakes too. I open up and read my published works and think based on my own scale “that’s a 4/5” or “that’s a 3/5”. I don’t give myself a 5/5 on my own scale. I try to earn it during the editing process though.

Listen: I self-published a book in 2008 under a pen name, then pulled it from digital shelves because I was scared. I sold 1 copy to myself. My grandmother was the only human who ever read it (I don’t count dogs). I honestly couldn’t afford to take the risk of printing and distributing more than that one, lonesome pre-reader copy. I chickened out. Any indie author I’m reading is brave. They didn’t chicken out. That’s already something to be proud of.

Anyways, back to our regularly schedule programming.