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Educating Maine's Starlit Communities Since 2004 | ||
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© Astronomy Institute of Maine All Rights Reserved | ||
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NIGHTTIME PHOTOS FROM ACADIA
These photos of the Ocean Drive Entrance Station in Acadia National Park capture the improvement made when the obsolete unshielded street lights were replaced during the 2002 renovation with modern full-cutoff designs.
Ocean Drive Entrance before (left) and after (right). Photos: Lanpher Associates, Inc.
The new energy-efficient lights enhance safety and visibility by directing 100% of their light towards the ground, where it is useful. The original unshielded lights sent light indiscriminately in every direction—including up into the sky and into the eyes of approaching drivers. As the human eye ages, it loses much of its ability to accommodate rapid changes in brightness. This glare can make it harder for senior citizens to spot pedestrians wearing dark clothes. Installing unshielded street lights with State of Maine funds became illegal in 1991.
Photo: Lanpher Associates, Inc.
Just off the Rt. 3 entrance to Acadia National Park, the Hulls Cove Visitors Center (above) provides an example of effective lighting that places light where it is needed. The parking lot and canopy area are well illuminated but also 100% glare-free.
Stray light allowed to shine up into the sky is a major source of the air glow called light pollution. As the transition from rural to urban nightscapes occurs, it can be seen as individual domes of light, as shown in the data below. Collected from Cadillac Summit by the National Park Service, the image reveals that individual light domes from as far away as Bangor are making a measurable impact on the sky, erasing the delicate arc of the Milky Way from the horizon. The red zone is in line with Rt. 3 as it heads off-island into the city of Ellsworth. Bangor lies in the same direction.
Over much of the country, such domes of light have become so common and so large that they obscure the entire sky. At this point two-thirds of the U.S. population can no longer see the Milky Way at all.
The Institute's Nightscape Survey System makes it possible for us to monitor changes in the size of light domes throughout Maine's communities.
Left: This is where stray light is not needed...Here over the Otter Creek Causeway in Acadia National Park, starlight from the Milky Way, faint light over 10,000 years old, is visible from the Acadia All American Road. Photo: Dr. Tyler Nordgren.
Right: The cold, clear nights of a Downeast winter provide some of the best stargazing opportunities in the country. On December 31, 2007, the Institute's astrophotographer, James W. Cormier, captured two major galaxies, two major comets, and two major star clusters in one extraordinary shot. All of these objects were also visible with the unaided eye—a fact that emphasizes the treasures available to all of us in our region's night skies.
The photo shows:
* In the center of the frame: NGC-752, an open cluster in Andromeda
* Below NGC-753: the Pinwheel Galaxy (M33), in Triangulum
* Below M33: the periodic Comet Tuttle, in Pisces
* In center right: the Great Andromeda Galaxy (M31)
* In the upper left corner: the still-wonderful Comet Holmes, in Perseus
* Below and to the left of Comet Holmes: the open cluster M34, in Perseus
Technical specifications: Piggyback mounted Pentax 67 with 105-mm f/2.4 lens stopped down to f/4, 25-minute exposure on Fujichrome 400X; scanned then processed in Photoshop Elements.
Click thumbnail to see the full-size image: 