Thursday, December 3, 2020

Lighting so bad it could win a prize

 Yesterday I joked on twitter that an image someone shared was so bad it should win a light pollution prize. Other twitterers responded with some of their own contenders. I thought I'd share them here:

Friday, October 9, 2020

Spanish language instructional video for the Loss of the Night app

Juan Pablo Uchima from the University of La Serena, Chile, created an instructional video for using the Loss of the Night app. Check it out!

Thanks so much for creating this Juan!


If anyone is inspired to do the same for another language, be sure to let us know!

Friday, September 18, 2020


On October 14-15, Helga Kuechly and I will be presenting a number of our projects related to citizen science and light pollution together with Sibylle Schroer from IGB at the Mitforschen! festival in Berlin. This post is mainly for people who might attend, but the links might also be interesting to other blog readers. The information is repeated in English below the German.

An unserem Stand werden wir ein tolles Experiment haben, das zeigt, wie eine Reduzierung der Beleuchtung die Sichtbarkeit auf der Straße verbessern und gleichzeitig die Lichtverschmutzung reduzieren kann. Wir haben auch interaktive Medienanzeigen, auf denen ihr Daten zur Lichtverschmutzung untersuchen könnt. Mit Radiance Light Trends könnt ihr testen, wie sich die Lichtemissionen weltweit ändern. Mit My Sky at Night könnt ihr die Nachthimmelbeobachtungen von Bürgerwissenschaftlern aus der ganzen Welt von 2006 bis heute erkunden und unseren Prototyp ausprobieren, der simulieren, wie sich ändernde Lichttechnologien auf den Nachthimmel auswirken. Darüber hinaus präsentieren wir das Projekt "Tatort Straßenbeleuchtung", bei dem es um Artenschutz durch umweltverträgliche Beleuchtung geht. Schließlich werden wir alle Teilnehmenden des Festivals einladen, im Rahmen unseres Nachtlicht-BüHNE-Projekts an einer bürgerwissenschaftlichen Aktivität teilzunehmen: entlang einer Straße in Berlin alle Lichtquellen zählen, die ihr sehen könnt. Diese Daten helfen uns, die Variabilität der Antworten von Person zu Person zu verstehen. Wir freuen uns darauf, dich zu sehen!


At our booth, we're going to have a cool visual demo that shows how reducing lighting can improve visibility on the street while reducing light pollution. We'll also have interactive media displays where you can explore data related to light pollution. With Radiance Light Trends, you can test how light emissions are changing around the world. With My Sky at Night, you can explore the night sky observations of citizen scientists from around the world from 2006 until today, and you can also play with a prototype system for simulating how changing lighting technologies changes the night sky. In addition, we will present the "Tatort Streetlight" project about species protection through sustainable lighting. Finally, we will invite everyone at the festival to take part in a citizen science activity as part of our Nachtlicht-BüHNE project: walking down a street in Berlin and counting up all the light sources that you can see. This data will help us understand the variability in responses from person to person. We look forward to seeing you!

Wednesday, July 1, 2020

Changes in light emissions during the COVID-19 shutdowns

At the start of the lockdown periods in Europe and North America, a few people speculated about what it might mean for changes in light emissions. I was skeptical that we would see much of anything.

Shortly afterwards, NASA showed some results for Hubei province in China:

We are still waiting for the monthly satellite data composites for February-April to come out, but I still don't expect to see much in most places. However, it turns out that there were some pretty dramatic changes in at least a few places around the world. The best example I've seen of this comes from Poland. Check out these two photos of Kraków, Poland, that Mateusz Windak posted on a Polish forum:

This work by Mateusz Windak is licensed under a Creative Commons Attribution 4.0 International License.
Click for the full size version.

Here's what Mateusz had to say about the photos:

The animation shows differences before and after midnight, when the Cracow city lights are switched off. After the switch off, only private light sources and the highway in the foreground remained. The lights were turned off for a month and a half from 00:00 to 04:00 each night due to the lack of traffic during the lockdown period of the COVID-19 pandemic. Currently, Cracow has stopped shutting down the lights, but some other cities are still continuing this practice.
The photos were taken from Wieliczka, a neighboring city, using a Mavic Air drone. They are four panel panoramas, the settings for each photograph are: 2s, ISO1600, f/2.8.

Thanks for sharing your photos Mateusz! I find it really impressive that in addition to the lights going off, you can also see the decrease in sky brightness

Friday, June 19, 2020

Panel discussion about light pollution and dark skies

A while back I was invited to be part of a panel discussion titled "Light Pollution & the Dark Sky Movement". Check it out:

[d]arc thoughts: Episode 4 | Light Pollution & the Dark Sky Movement from [d]arc media on Vimeo.

Thursday, June 11, 2020

Loss of the Night app video tutorials

A group of undergraduate students from Worcester Polytechnic Institute recently produced tutorial videos for using the Loss of the Night app. They made separate videos for the Android and iOS versions. Feel free to share them!



Big thanks to Aaron, Kai, Ryan, and Vinit for producing these videos!

Tuesday, June 9, 2020

Removing natural light from nighttime satellite images

My student Jacqueline Coesfeld recently developed an analysis that will be interesting for readers of the blog who work with satellite data. I summarized it in a series of tweets. You can click on the tweet to read the thread, or see the unrolled version here.