Cenizo Journal Winter 2021 | Page 9

and impact . According to Lee , “ It takes very little light to mess things up in a nighttime photo .”
The most effective way to improve night sky quality over such a large region is through increased individual awareness and improved practices . Leading the way for this is Texas Local Government Code Title 7 , Chapter 229 ( 2011 ) which directs municipalities “ located in a county any part of which is located within 57 miles of a major astronomical observatory ,” such as the McDonald Observatory atop Mount Locke in Fort Davis , to adopt night-sky friendly ordinances . Seven Texas counties have and are now updating their codes . But while statutory protections exist , and awareness is improving , night sky advocates living within the scope of the statute believe more could be done to improve understanding and reduce trespass light .
The creation of the Big Bend Dark Sky Reserve is good news for the scientific , economic and recreational sustainability of our region , but to focus solely on these attributes overlooks the important health and well-being benefits of high-quality night skies .
Humans and wildlife depend on Earth ’ s natural light and dark cycles , which govern biological processes and life-sustaining behaviors . Exposure to artificial light after sunset is an entirely unnatural occurrence which confuses biological regulation . Moreover , the invention of Light Emitting Diodes ( LEDs ) decouples artificial lighting from cost as a factor . An unintended consequence of increased LED use has been Earth ’ s vanishing night sky . Images of the United States captured by NASA and others depict dramatic changes . From space , Earth might appear to be a beautiful , brightly illuminated object . But imagine trying to sleep where there is no natural night , ever . Much less trying to see a single star from a place where the skies are overly lit .
The scientific evidence indicates our nearly ubiquitous exposure to artificial light at inappropriate times has negative health consequences . Medical , biological , and social scientists continue to discover how artificial light activates our central nervous system , thereby disrupting biological circadian rhythms . Circadian rhythms are naturally recurring physical , mental and behavioral changes which occur on a twenty-four-hour cycle even in the absence of light . They are essential to various biological and cellular processes . Light in the blue and bright white range , such as those from many ( but not all ) LEDs , monitors , displays and cell phone screens is especially problematic .
Disrupted circadian rhythms caused by nighttime artificial light exposure affects aspects of physiology with direct links to cell cycle regulation , DNA damage response , and metabolism . Health impacts of light pollution may include insomnia , obesity , depression , sleep disorders , diabetes , chronic illnesses and even certain types of cancers , including breast cancer .
These findings are so serious , the American Medical Association House of Delegates issued a 2012 policy statement on nighttime lighting and human health published in the American Journal of Preventative Medicine . The AMA policy statement on exposure to artificial light after dark advocates for a reduction in unnecessary lighting and technologic solutions to ensure that when we use lighting , it optimizes visual performance while minimizing circadian disruption .
Unfortunately , the problem of artificial light pollution is extensive and expanding , even though it is easily mitigated . A 2016 atlas of the night sky published by astronomy
Limpia Hotel , Fort Davis , Texas Before and After Night Sky Friendly Retrofit . Bill Wren
researcher Fabio Falchi with the Light Pollution Science and Technology Institute in Thiene , Italy depicts a planet where more than 80 % of the land area is so light polluted from artificial light that the Milky Way is invisible . According to Falchi , 99 % of the combined U . S . and European population suffer the effects of light pollution . Another study estimates light pollution expanding globally at a rate of approximately 2.2 % per year ( Kyba , et al ., 2017 ).
Projects such as the proposed Big Bend Dark Sky Reserve will be an important part of the light pollution solution because they demonstrate how to protect and recover night sky quality . Light pollution can be easily , affordably and immediately reversed , “ with the flick of a switch ,” as it were , and much more quickly than air , water , or land pollution . With increased awareness and a few basic changes , such as only illuminating areas when in use , shielding bulbs and filaments and choosing warmer light tones , we all can help protect and restore night sky quality .
Night sky friendly lighting practices do not sacrifice illumination and security . A 2015 study published in the Journal of Epidemiology and Community Health found no reductions in accident or crime rates attributable to increased street lighting . At best , the connection between light at night and crime reduction is weak . So , more light isn ’ t necessarily better .
Continued on page 10 .
Cenizo Winter 2021