New Technology Aims to Fight Light Pollution and Restore Clear Views of the Night Sky
Light pollution has become a growing threat to astronomy, but a new streetlamp technology could potentially solve this problem and allow for clearer views of the night sky. Light-emitting diodes (LEDs) have gained popularity over the past two decades due to their energy efficiency, consuming only about 10% of the electricity required by traditional incandescent lights and lasting up to 25 times longer. However, LEDs are much brighter than old-fashioned light bulbs, causing the light to scatter through the Earth’s atmosphere and intensifying the glow of the sky.
This light pollution issue has significant consequences for astronomical observatories, which in the past were typically constructed in dark and remote locations. Now, these observatories are seeing fewer stars than before, offsetting the improvements made through advancements in telescope technology. A recent study found that stars are disappearing from the sky at an average annual rate of 10%, affecting even the most remote observatories worldwide.
German startup StealthTransit has tested a solution to combat this problem. The company’s founder and CEO, Vlad Pashkovsky, explained that “modern telescopes are highly sensitive and feel the impact of outdoor lighting of cities located at the distance of 50 or even 200 kilometers [30 to 120 miles]. This means that virtually every observatory on Earth either already needs, or will need in the future, protection from the light of large cities.”
StealthTransit’s solution involves three key components: a device that makes LED lights flicker at a high frequency imperceptible to the human eye, a GPS receiver, and a specially designed shutter on the telescope’s camera that can synchronize with the LED lights. The GPS technology guides the telescope’s shutter to open only during the brief moments when the LED lights are switched off.
Experiments conducted on a 24-inch (60-centimeter) telescope in the Caucasus Mountains, Russia, showed impressive results. The technology, named the DarkSkyProtector, reduced unwanted sky glow in astronomical images by 94%. Pashkovsky confirmed that “the telescope was seeing almost a dark sky” during the tests. Additionally, the technology has the potential to filter out lights from nearby towns and villages, as well as those surrounding the observatory itself.
While the idea of refitting an entire town with devices that allow lamps to blink may seem impractical, Pashkovsky assured that most existing LED lights can operate in the blinking mode. Moreover, new lamps designed specifically with sky protection in mind would be no more expensive than current LED technology. The most costly element of the DarkSkyProtector system is the telescope shutter, which needs to be lightweight and agile enough to blink approximately 150 times per second.
Although StealthTransit’s technology is not yet ready for commercial use, the company aims to have a product suitable for the world’s best telescopes within the next five to seven years. This innovation brings hope for restoring clear views of the night sky and preserving the wonders of astronomy for future generations.