Adler examines street light switchover: Can the brightness be turned down?

Chicago lit, at night Photo credit Getty Images

By Jim Gudas

(WBBM NEWSRADIO) — Chicago’s Adler Planetarium is working to reduce light pollution in Chicago.

Michelle Nichols, director of public observing, said the museum and research center is studying whether the switch from sodium to LED street lamps in Chicago is reducing or increasing light pollution.

The city’s night sky isn't as orange as it was with the sodium bulbs, but the LEDs might actually have a greater effect on our eyes, she said.

”The human eye is most sensitive to blue light, and LEDs give off a lot of blue light,” she said.

The Adler is going high in the sky to measure how much light pollution comes from the LED street lights. It is using high-altitude balloons with instruments to make measurements.

Nichols says some homeowners and businesses are switching to LEDs for outdoor lighting, but they may be installing systems that are brighter than necessary.

"They might be taking out a 100-watt incandescent bulb and putting in a 100-watt LED bulb. They are just blazingly bright, and if you're using less electricity to run them, people have been putting up more lights,” she said.

Nichols says the Adler Planetarium hopes to reduce light pollution by educating the city, homeowners and businesses on the best and most efficient use of LED lights. For more information, visit the Adler's website.