There is a new urban dark sky place, one of only three total, and it’s the largest in the world. Palos Preserves is just outside the city limits of Chicago, but still in Cook County, on the south side and officially earned the designation in late August from the International Dark Sky Association (IDA).

The IDA recognizes dark sky places all over the world each year as part of its program to encourage communities to conserve the night sky. Palos Preserves is near Chicago, an urban setting with significant artificial light at night, making it’s designation unique and rare.

The Adler Planetarium played a major role in helping Palos Preserves earn this designation through data collection, night sky monitoring, and light pollution guidance. As part of the application process, area teens in the Far Horizons Stratonauts program helped gather and compile data using images taken from the International Space Station, satellites circling the Earth, and special cameras they built to monitor the night sky.

Help from the Adler also came in the form of advice and guidance regarding a lighting management plan for the Forest Preserves of Cook County’s Palos Preserves to implement. Numerous organizations, including the Adler, in Chicago have made great strides in guidance related to lighting in order to reduce light pollution across the city. Before temporarily closing due to COVID, the Adler debuted Chicago’s Night Sky, an exhibit dedicated to our connection with the stars that also featured ways to preserve dark sky.

Data showed that the park emits 1,000 times less light than downtown Chicago, a difference that is clearly visible in nighttime satellite images. As one of the largest parks in the county’s forest preserve program, Palos Preserves covers an area of over six thousand acres and plenty of place for stargazers to spread out.

The Forest Preserve is currently working with the Adler to organize nighttime stargazing and astronomy based events to celebrate the new dark sky status. Outside of these events, guests can take advantage of the dark skies through overnight camping opportunities arranged directly through the Forest Preserve.