In short

• Reflect Orbital ran a land-based test near Lone Pine, California, casting light brighter than the full moon onto a search and rescue team running drills.
• NHTSA plans to rewrite its headlight glare rules, although an Insurance Institute for Highway Safety study found glare in only 0.1% to 0.2% of crash data across 11 states.
• A Journal of Quantitative Criminology study found Newark’s LED streetlight conversion cut nighttime outdoor violent crime 46% in the first six months, but the effect wore off.
• A European Heart Journal study of UK Biobank data linked the highest nighttime light exposure to heart changes and higher cardiovascular risk. It is observational and cannot show causation.
• Cherry Springs State Park in Pennsylvania completed a $5.2 million renovation.

Hi everyone. This month, I was glad to be joined by three really deep thinkers on this topic: Ari Isaak, of EvariLabs, Josh Sokol, a freelance journalist, and from Parc-National-Entre-Sambre-et-Meuse in Belgium, Nicolas Goethals. You can hear all of the thoughtful discussion by checking out this month’s episodes: Ignore Ecological Light Pollution! and Chipping Away at the Public Commons.

As a reminder, Light Pollution News is a listener-supported show, which means that we take no outside money and wholly rely on the support of our listeners to keep this thing going! See LightPollutionNews.com/Support to learn more. If that’s not your thing, kindly share this column with anyone whom you think may benefit from it.

Reflect Orbital Tests Brighter Than Full Moon Light Near Lone Pine, California

This month, Reflect Orbital ran a land-based test south of Lone Pine, California. The company cast a light source brighter than the full moon off of a lookout point in the Sierras onto a search and rescue team running drills.

NHTSA to Rewrite Headlight Glare Rules Despite Low Glare Share in Crash Data

In the US, NHTSA announced plans to rewrite its headlight glare rules despite an Insurance Institute for Highway Safety finding that headlight glare accounted for only 0.1% to 0.2% of crash data across 11 states from 2015 to 2023. The move followed complaints from various outlets including Congressional representatives, the Soft Lights Foundation, and an AAA survey where six out of ten drivers said glare was a problem.

Newark LED Streetlights Cut Nighttime Violent Crime 46%, but the Effect Wore Off

A crime study in the Journal of Quantitative Criminology examined Newark, New Jersey’s LED streetlight conversion in high-crime areas from 2019 to 2021. From 43 million observations, models showed a 46% drop in outdoor violent crimes at night during the first six months. The bad news: the effect wore off, with violent crimes rising 54% about two years later. LED streetlight conversion did not affect property crimes.

Breckenridge Presses Dark Sky Compliance and Weighs Buying Xcel Streetlights

Breckenridge, Colorado reached 91% lighting compliance after sending 568 violation letters this year. To date, the town has converted 63% of its 1,539 streetlights to dark-sky-friendly fixtures. 167 fixtures belong to utility Xcel Energy, which rejected the town’s dark sky package due to a specification mismatch. Breckenridge is currently weighing a buyout of the Xcel-owned streetlights.

Review Finds Measuring Light Pollution’s Ecological Impact Is Still Difficult

A review in Nature Reviews Biodiversity surveyed five years of ecological light pollution research. Measuring light’s ecological impact remained genuinely difficult because most tools were built to resolve related human questions.

German Study Finds Shielded 2200K LED Road Lights Attract Fewer Insects Than Sodium

A German study found shielded 2200K LED road lights attracted 57% fewer insects than high-pressure sodium lights, with the biggest gains during late evening and midnight hours. See our Ecology News for the full slate of this month’s ecology-related research and stories.

Belgium’s Entre-Sambre-et-Meuse National Park Removes Streetlights for a Dark Corridor

Belgium’s Entre-Sambre-et-Meuse National Park completed a project to remove 79 streetlights selected for low safety value and proximity to natural areas, at a cost of roughly $344k. The goal is to build a dark corridor supporting habitat restoration.

Cherry Springs State Park Completes $5.2 Million Dark Sky Renovation

Cherry Springs State Park in Pennsylvania completed its $5.2 million renovation.

Lakeview West Near Little Rock Is Built Without Streetlights

There’s a planned community called Lakeview West, which sits 30 miles from Little Rock, Arkansas. This community was purposely built without streetlights and equips homes with downward-facing exterior lighting. At the time of recording, 40 homes have been sold at around $500,000 each.

Nighttime Light Exposure Linked to Heart Changes in European Heart Journal Study

A European Heart Journal study used UK Biobank data from 11,000 people who wore wrist light sensors and later received cardiac MRIs. The highest nighttime light exposure group showed a 2.4% greater left ventricle mass, 1.5% thicker heart walls, and 2% lower myocardial contraction. A larger 73,000-person Biobank subset showed a 29% higher risk of heart failure, 33% higher stroke risk, and 26% higher cardiovascular death risk versus those with no nighttime light above 3 lux. This type of study can’t assess causation, but the evidence kept pointing the same direction.

Quick Answers From This Month’s Light Pollution News

What was Reflect Orbital’s test near Lone Pine, California?

Reflect Orbital ran a land-based test near Lone Pine, California, casting a light source brighter than the full moon from a lookout point in the Sierras onto a search and rescue team running drills.

Why is NHTSA rewriting its headlight glare rules?

Light Pollution News reported that NHTSA announced the rewrite after complaints from Congressional representatives, the Soft Lights Foundation and an AAA survey in which six in ten drivers called glare a problem. An Insurance Institute for Highway Safety study found glare in only 0.1% to 0.2% of crash data across 11 states.

Did LED streetlights reduce violent crime in Newark?

For a while. A Journal of Quantitative Criminology study of Newark, New Jersey’s LED streetlight conversion in high-crime areas found a 46% drop in nighttime outdoor violent crime during the first six months. The effect wore off, and violent crime had risen by about two years later. Property crime was not affected.

Is nighttime light linked to heart disease?

A European Heart Journal study of UK Biobank data found associations. In a 73,000-person subset, people with the highest nighttime light exposure had a 29% higher risk of heart failure, 33% higher stroke risk and 26% higher cardiovascular death risk than people with no nighttime light above 3 lux. The study is observational and cannot show causation.

How is Breckenridge, Colorado enforcing dark sky lighting rules?

As reported this month, Breckenridge reached 91% lighting compliance after sending 568 violation letters this year and has converted 63% of its 1,539 streetlights. Of those, 167 belong to Xcel Energy, which rejected the town’s dark sky package, and Breckenridge is weighing a buyout.