Star Light, Star Bright
Location: Retzer Nature Center; S14 W28167 Madison Street
Before you begin, you may wish to go inside the Retzer Environmental Learning Center to pick up a map of the trails, but it is not necessary to use the map in order to find the letterbox. Note: The pink Nature Trail Loop found on the map is referred to as the red trail in directions since the markers along the trail are red.
Begin outside the Environmental Learning Center at the Environmental Learning Center Trail Head. The building at the Retzer Nature Center holds the Charles Z. Horwitz Planetarium, which allows visitors to view a simulation of the night sky and learn about astronomy. Planetariums, like the one at the Retzer Nature Center, are the only way some people can see the stars in the sky because of light pollution. In fact, estimates by the British Astronomical Association and the Campaign for the Protection of Rural England show that 85% of the British people cannot see the stars because artificial lighting blots out the night sky. England is not the only country where people are struggling to see the stars; one-fifth of the world’s population can no longer see the Milky Way, and two-thirds of the population in the United States no longer have a visible view of our own galaxy.
Start your search for the letterbox by walking to the left from the large map at the Trail Head along the Green Outer Hiking Loop. When the paved trail veers to the right, continue following the green trail that is paved with woodchips to the left. Darkness is easy to find at the Retzer Nature Center at night, but many cities have lights on all the time and darkness is hard to find.
Continue following the green hiking loop through the wooded area and curve to the left through the clearing, still following the green trail markers. Continue past the Oldfield Planting sign and the bench in memory of Dorothy Doyle, and keep climbing up the hill. When you get to an area where several trails meet, continue straight ahead onto the yellow prairie vista trail and look for the bench and wooden rail at the top of the hill. Go to the bench and sit down for a moment and take in the view. Now imagine what the view would look like at night. From this point, many stars would be visible in the sky above. However, stars are not visible in all areas because of light pollution. Light pollution, also known as photopollution or luminous pollution, is defined as excessive or annoying light that intrudes on a natural or low light setting, and it is most prominently found in heavily populated or highly industrialized areas. The light that is reflected into the atmosphere, especially near heavily populated areas, is known as sky glow; much of this is caused by outdoor fixtures that send their light upward instead of onto their target, resulting in wasted energy. Although it cannot be seen during daylight, the sky glow from the reflection of lights from the surrounding area of Waukesha into the atmosphere can be seen from the Retzer Nature Center when darkness falls. Other types of light pollution include light trespass and overillumination. Light trespass occurs when light enters an area where it is not wanted, like a neighboring property, and this also causes excess use and energy waste known as overillumination.
With your back to the bench and wooden rail, move away from the vista and take the yellow trail to the left. You should notice the numbered marker 4 a few steps down the trail. As you continue along the yellow Prairie Vista Trail, think about what else may be affected by light pollution. It is not only a problem for astronomers and stargazers, but plants, animals, and humans are impacted by the increasing light pollution in our world.
When the trail splits at marker 7, turn left where you see marker 9. After you turn onto the trail, look for any flowers and plants that are growing nearby. These plants depend on the pattern of the sun and moon to know if it is day or night, but they can be confused if an artificial light makes them think that it is day all night long. Some plants have been found flowering at night or dropping leaves at the wrong time of the year as a result of light pollution.
When you reach the end of the trail you are on (it may seem like you are bushwacking a bit, make sure you go past the fence), turn right onto the tractor trail and continue until you find the red Nature Trail Loop. The marker has both red and white where you will turn left. Along the red trail you should notice the number markers counting down from 16. Go past the red trail marker on your left and look for marker 14. Take a left on the trail immediately before the marker 14. As you enter the wooded area on the black trail (not marked where you enter it) keep watch for any animals that may be living there. Many animals depend on daylight and darkness in order to function normally, and they can become confused if lights are on all night. Some wildlife, including moths, are attracted to light, and when they flock to the light they increase their chances of being preyed upon and reduce their opportunity to find a mate. Animals instinctively know when to hunt, sleep, mate, and give birth from the natural light of the sun, and the timing of these events can be thrown off if artificial lighting disturbs their circadian rhythms. Nocturnal animals like frogs and salamanders have less time to mate and reproduce if their habitat has artificial lighting that makes them think it is still daytime, and glowworm and fireflies can also struggle to mate and reproduce because they cannot see their mates in an area filled with artificial light at night. Birds that live around street lamps have been seen chirping past dark, and many birds die each year after flying into tall towers or colliding with buildings that reflect artificial lighting.
Continue along the black trail through the woods, and keep going on the black connecting trail by turning right when you come to a clearing. Walk along the edge of the trees until you come to the Green Outer Hiking Loop, and then take a right on this trail. Walk along this trail until you come to the Retzer Creek. After you cross the bridge over the Retzer Creek, continue over the wooden path where looking to your left you will realize that human impacts are not far away from the wildlife at the Retzer Nature Center. The highway follows closely along this path, and there should be a house in view. Humans are also affected by light pollution. Overillumination and common fluorescent lighting in many workplaces can cause headaches, stress, fatigue, and even elevation of blood pressure by 8 points. Darkness is important for the production of melatonin, and when humans do not have enough exposure to darkness, their risk of breast cancer can increase because the normal nocturnal production of melatonin is suppressed. Leaving lights on at night can also lead to hyperactivity, especially in children.
Continue following the green trail. You may notice a purple trail marker to the left, but keep walking over the wooden path after the purple trail joins the green trail. Further ahead you will notice landscaping stones on the left. Continue following the purple and green trail and then turn right onto the red trail when the wooden walkway steps down. You should notice marker 7 to the right side of the trail.
Light pollution impacts our world in a variety of ways, but there are ways to limit its effects on humans and other species. Dave Crawford, the cofounder of the International Dark-Sky Association, notes that “there are hundreds, if not thousands, of light pollution ordinances nationwide,” and most of these limit upward-shining light, overlighting, and light trespass. Even with these laws, there are many people who do not take steps to reduce the impact of their outdoor lighting. You can reduce light pollution by using lights with the minimum necessary intensity, using timers to turn lights off when they are not needed, and installing fixtures that focus lights toward their intended target. Low-pressure sodium lamps, shields to direct the light, and lamps that filter ultraviolet light are also options that help reduce the impacts of light pollution on plants, animals, or other humans.
Continue along the scenic red trail until you find a bench next to a sign about improving our water. Sit down on the bench and use what you learned about light pollution to fill in the words and decipher the code.
1. Place inside where you can see stars
_ _ _ _ _ _ _ _ _ _ _
D J Q X V H Q B S Y P
2. Another name for light pollution
_ _ _ _ _ _ _ _ _ _ _ _ _ _
D K M H M D M J J Y H S M X
3. Light that does not come from the sun (fake)
_ _ _ _ _ _ _ _ _ _
Q B H S Z S T S Q J
4. Light reflected into the atmosphere(especially in heavily populated areas)
_ _ _ _ _ _ _
W A R E J M O
5. This can increase by 8 points from exposure to workplace lighting
_ _ _ _ _ _ _ _ _ _ _ _ _
I J M M F D B V W W Y B V
6. This is produced at night and suppression of its production can increase risks of cancer
_ _ _ _ _ _ _ _ _
P V J Q H M X S X
7. The Milky Way is ours
_ _ _ _ _ _
E Q J Q C R
Past marker H K S B H V V X, look J V Z H for a small D S J V of J M E W that is D V B D V X F S T Y J Q B to the trail. The J V H H V B I M C is hidden Y X F V B the J M E W about Z M Y B feet from the H B Q S J.
Once you have figured out the message, continue along the red trail past an uprooted tree by marker 12 on your left until you find marker 13, and then use the decoded message to find the letterbox. When you find the box, stamp in and return the letterbox to its place . To find the exit, follow the red trail back past the bench the way you came in on the red trail. Go straight on the wodden trail past marker 6 and curve to the right toward the wooden bridge. The trail will lead you back to the Environmental Learning Center.
Topical Index Listing of Information Sheets. Retrieved April 19, 2006, from International Dark-Sky Association Website: http://www.darksky.org/infoshts/istopic.html
Feder, T. (2005). Limiting Light Pollution Is Ongoing Challenge. Physics Today, 58(6), 24-36.
Light pollution. Retrieved April 19, 2006, from Wikipedia Web Site: http://en.wikipedia.org/wiki/Light_pollution
Smith, J. (2005). Starry Starry Nights. Ecologist, 35(9), 56-62.