Sunday, October 26, 2014

Photos from our light over Linz, Austria

Tonight we did a measurement flight over the cities of Linz and Wels in Austria. The goal is to make a mosaic image of these ares of Land Oberöstereich, in order to understand the region's waste light emission. We have done something very similar for Berlin.

I wanted to share a few photos from tonight's flight:

The project is a research collaboration between Freie Universität Berlin, Universität Wien, and Land Oberöstereich. The flight costs were paid for by Land Oberöstereich.

Friday, October 24, 2014

Hesitations on the 2014 Nobel Prize in Physics and its negative impact on human health – was this the aim of Nobel Prize?

This guest post was written by my colleague, Professor Abraham Haim, from The Israeli Center for Interdisciplinary Research in Chronobiology, University of Haifa. Professor Haim is also the vice chair of the Loss of the Night Network (LoNNe). The views presented here are his own. My comments regarding the Nobel decision are available here.

Recently the 2014 Nobel Prize in Physics was given jointly to Isamu Akasaki, Hiroshi Amano and Shuji Nakamura "for the invention of efficient blue light-emitting diodes which has enabled bright and energy-saving white light sources".  This is of course a huge scientific achievement and they should be congratulated for receiving this prestigious prize. Many of us in the scientific community would be delighted with being awarded the Nobel Prize and I am sure that when we carry out research, somewhere in our mind we think that maybe the results could bring us closer to this desired prize.  However, this recent award raises more fundamental questions about how the negative impacts of such research should be acknowledged and the difficulties created when such prizes disproportionately raise public awareness about their positive applications.
To the best of my knowledge the Nobel Prize foundation was established in response to the concerns of Alfred Nobel, that his inventions (notably explosives) had inevitably let to large-scale loss of life through diverse military applications.  The spirit of the prizes was therefore to reward research that supported global peace, health and other benefits related to human wellbeing. What is irritating in the decision of the committee awarding the prize to the three distinguished physical scientists is the apparent lack of awareness that LED lamps deliver energy saving at the sake of our environment and health. Exposure to blue light from LEDs has a high health risk well known in environmental literature, and scientists are looking for ways to eliminate this wavelength emission from LED bulbs. A question to be asked in regards to the committee decision is: Shouldn’t the members of such a distinguished group pay attention to environmental and health problems arising from the invention? In the case of light pollution, many of the leaders of the high profile campaign for dark skies come from the discipline of astrophysics, as in Western Europe and North America it’s difficult to observe stars. LED illumination is increasing the problem due to its intensity and the aggressive way it penetrates our lives. The potential negative medical impacts such has epigenetic modification would be recognized only after ten years or more, if I am correct. So far we have demonstrated that blue LED can suppress melatonin production and among the known sources of illumination this is the most efficient one. The neuro-hormone melatonin produced in the pineal gland during the dark phase of the 24h cycle is a “jack of all traits”, but is particularly important for our sleep, it is also an efficient anti-oxidant and anti cancer agent in regards to breast and prostate cancer. In June 2012 the American medical Association passed a resolution that light at night is a source of pollution; were the distinguish committee members not aware of this resolution?     
In our modern lifestyle most of the new electronic devices we use include LED in their screens or operation light indicator and many of these find their way into the bedrooms of young people who are exposed to this illumination during their sleep, when they need to be in the dark to produce the neuro-hormone melatonin. Looking directly to the source of LED illumination may also destroy our retina as indicated by results of studies carried out on this topic, which showed that LED illumination can result in death of retinal cells. LED technology as a source of illumination in public spaces is under discussion where those with an environmental approach would argue that we need more research in regards to smart use of this technology. Awarding a Nobel Prize at this stage is a mistake, as the unintended consequences of LED lighting are only starting to emerge. The information given here is mainly intended to help make the public aware of the danger of using LED illumination, yet there is a basic awareness of this issue within the scientific community, which should have been considered by the prize committee.  It cannot be said that “we did not know”.  I feel like the child from the story by Hans Christian Andersen, who did not pretend to admire the “new clothes of the king” and shouted “The king is naked”.                  
As has happened with past awards there is a strong risk that the integrity of the Nobel Prize may be undermined, when the large-scale negative impacts of LED lamps are realised.  In fact, surely the origin of the Nobel Prize itself points to the argument that researchers and inventors should not only seek to develop new technologies, but also to address their weaknesses and to avoid unintended consequences for society.   

Wednesday, October 22, 2014

Your chance to see Berlin at night from the air

I've flown over Berlin at night many times as part of our research campaigns to understand the light emission of the city. It's a very cool experience, and for a short time, it's open to everyone.

During the celebration of the 25th anniversary of the fall of the Berlin Wall, Air Berlin is operating a special flight over the city. In addition to the many historic and modern landmarks visible from the air, thousands of lit balloons will mark the former path of the wall through the city.

I suspect that the balloon display will be more moving from the ground than from the air. But I think this is a great opportunity, and I can highly recommend the experience to anyone who loves Berlin!

Tuesday, October 14, 2014

GLOBE at Night observing period begins tonight

Once again the moon has gotten out of the way in the evening, and it's possible to observe skyglow via GLOBE at Night, the Dark Sky Meter app, or the Loss of the Night app. This early evening moon free period runs until October 23.

Friday, October 10, 2014

Moon phase calendar for 2015

Loss of the Night app user Andrew Cool from Australia has once again produced his very cool calendar of the phases of the moon in 2015:

You can download his original images in high and low resolution on his SkippySky website.

If this is your first-ever visit to the blog, welcome! The blog is about a citizen science app called "Loss of the Night". We need your help to understand how changes in street lighting technology are changing the night sky. You can read our introduction to the blog here, and instructions on how to use the app here.

There's lots more to see, including:
You can see bring up our entire photo series via this link, and all of our posts about the moon here. Thanks for visiting!

Thursday, October 9, 2014

Last night's lunar eclipse, viewed from space

Each night, an instrument called VIIRS DNB takes visible band images of the entire Earth. When the moon is up, it's really easy to see the patterns of the clouds, and when the moon is set you can basically only see the artificial light from cities. But what happens when you have a lunar eclipse? This:

2014/10/08 lunar eclipse viewed by VIIRS DNB by Christopher Kyba & NOAA
is licensed under a Creative Commons Attribution 4.0 International License.
Based on a work at
Image and Data processing by NOAA's National Geophysical Data Center.

As the Earth's shadow darkened the face of the moon, there was progressively less light for DNB to be able to see land, clouds, and sea. As a result, with each pass of the satellite the image gets darker. The satellite takes about an hour and a half to go around the Earth, so the effect lasts over 2-3 passes. Since we don't have a geostationary satellite capable of imaging the Earth in moonlight, it's not yet possible to produce an video, like this one of a solar eclipse.

For the next several days, you can access the full (giant) resolution image from NOAA. You can get an in-between resolution image from my personal webpage.

If you'd like to see images of hurricanes imaged by VIIRS DNB with moonlight, follow @DanLindsey77 on twitter:

Note for new visitors: This blog is about the Loss of the Night citizen science app, which lets regular people measure how bright the sky is by looking at stars. The goal of the app is to track how the brightness of the sky changes as LED lighting is implemented worldwide. The app is free, and can be downloaded for Android phones. An iPhone version is in development and will come out soon.

Tuesday, October 7, 2014

The promise and the peril of LED lighting

Wonderful news for Isamu Akasaki, Hiroshi Amano, and Shuji Nakamura, who won the physics Nobel Prize today "for the invention of efficient blue light-emitting diodes which has enabled bright and energy-saving white light sources"!

When used for outdoor lighting, white LEDs (which are built out of blue LEDs) have two incredibly useful properties. First, they can be directed more carefully than the older gas discharge tube lamps, and that means that with good design it's possible to put light on a walkway and the surrounding areas without shining lights up into the sky, into people's bedroom windows, and without glaring down the street. Second, they can be turned on and off and dimmed instantaneously. This means that dusk-till-dawn lighting can become a thing of the past, and in the future city lighting will hopefully be delivered on-demand, rather than left burning on every street all night long.

 It's possible to imagine a future in which driverless cars run without headlamps (the car itself can be dimly lit to make it visible), pedestrian and cyclist lights provide more uniform lighting at greatly reduced light levels, and the sky above even large cities once again glitters with thousands of stars.

But unfortunately, this future won't come about simply thanks to the genius of the physicists honored today. It will take the combined efforts of hundreds of thousands of other lighting innovators: engineers, designers, city planners, and perhaps most importantly, lawmakers. The problem is that without careful design and planning, high efficiency LEDs can end up looking like this during the night:

Exposure set to match street level
Exposure set to image the screen

At the corner of one of the busiest pedestrian crossings in Berlin (Kurfürstendamm and Joachimstraße), drivers turning right through a crosswalk are blinded by an LED screen that's left running at daytime appropriate levels during the night!

Due to the remarkable compactness of LEDs, the glowing area of the lamps themselves are far brighter than many older style lamps. This, combined with their greater component of blue light can make them far more glaring, a problem that disturbs both drivers and pedestrians alike on many poorly lit LED streets.

Interesting architectural lighting can be accomplished using highly efficient 1 Watt LEDs. But if it's poorly designed, it blind visitors to the city coming out of a train station into an unfamiliar surrounding, such as this problematic area just outside of the Alexanderplatz station in Berlin:

Exposure adjusted to street levels

Exposure auto-set by camera

In the coming decade, LED lighting is going to entirely change the way we light both indoor and outdoor spaces, and for that we should most certainly thank today's prizewinners. But will we actually save energy - or just waste extra light? And will we have a more pleasant living environment? The answers to these questions will depend mainly on their implementation.

Note for new visitors: This blog is about the Loss of the Night citizen science app, which lets regular people measure how bright the sky is by looking at stars. The goal of the app is to track how the brightness of the sky changes as LED lighting is implemented worldwide. The app is free, and can be downloaded for Android phones. An iPhone version is in development and will come out soon.