On October 18, Crossroads at Big Creek will celebrate the Wisconsin Science Festival with Spectrum Day.
Several weeks ago, I mentioned to a friend that I saw the visible light spectrum in the form of a rainbow, arching over the Crossroads preserve. She replied that she had seen the same rainbow.
According to one my favorite naturalist/philosophers, Kermit the Frog, “Rainbows are visions, but only illusions.” And really, my friend did not see the illusion I saw. I find this enchanting. Each person’s vision of a rainbow is unique….different is some way to the rainbow vision anyone else is seeing.
Your personal rainbow may appear to you if water droplets are in the air when the sun is behind you. And for the sun to be behind you, it must be low in the sky. You won’t see rainbows at high noon or even in late morning or most of the afternoon. The rainbow will always appear in the direction opposite the sun, so in late afternoon, when the sun is setting in the west, the rainbow appears in the east. Rainbows happen when light passes through raindrops.
Most of us visualize a raindrop as a tear-shape…pointed at the top and fat at the bottom. Actually, most raindrops are spherical. Sometimes really big raindrops get flattened a bit by air resistance, but the raindrops the produce rainbows tend to be perfectly round. So the white sunlight enters the tiny sphere, some of the light reflects (bounces off) the drop’s inner surface, and is bent as it comes back out. Similar to what happens in a prism, when the sunlight is reflected and refracted, colors are revealed. Thousands of different gradation of color form the spectrum and these colors blend into one another in a glorious multicolored curve.
What the illusion you see depends on where you are standing, how tall you are, how close you are to the rain, how high the sun appears in the sky, if the raindrops have salt in them, and if you are seeing the rainbow over land or over water. Each of these conditions will slightly change the rainbow. Because no two sets of eyes could ever be in the exact same place, the light which is bent reaches you at an angle that is slightly different from that perceived by someone right beside you. Not much different…but enough to make it unique.
The Rainbow Room (also known as the Entry Level of the Collins Learning Center) will have stations where pre-school, Kindergarten, and primary aged students can celebrate Spectrum Day. From 2:00-3:00 volunteers will involve young learners in hands-on activities relating to rainbow and the spectrum. Older student will go beyond the visible light to explore the electromagnetic spectrum. Whether or not they are aware of it, “invisible light” is very important to their lives. They listen to the radio, control their televisions with a remote, they talk on Cell-phones, heat their snacks in microwave ovens and they from time to time need an X-ray. Presenters will help them understand light waves and their uses. A fire truck will be in the Collins Learning Center parking lot, and firefighters will demonstrate their thermal imaging camera to detect he infrared range.
“Demonstration and Discussion of Spectroscopy” will be offered at 3:00 by Dr. Ray Stonecipher and Dave Udell at the Stonecipher Astronomy Center. This presentation will be appropriate for high school students and older, though younger learners will be fascinated by the lights. In the evening, the Door Peninsula Astronomical Society will offer a Planetarium Show at 7:00 in the Stonecipher Center and if skies are clear, will host a Night Sky Viewing in the StarGarden at 8:00. Again, Kermit says it best: What’s so amazing that keeps us stargazing and what do we think we might see? Someday we’ll find it, the rainbow connection.” We invite dreamers and learners of all ages to find the rainbow connection on Spectrum Day at Crossroads.
On Sunday, we invite the community to join Rotary Interact in pulling buckthorn along our new trail. There will be two work parties. One starts at 1:30 and on starts 30 minutes after the end of the Packer Game. No experience is necessary, but heavy work gloves are important. Meet at the Collins Learning Center.
That evening, we’ll have a Open Fire Pit Gathering between 5:00-7:00. Bring the family and the fixings for your dinner. Friends of Crossroads will have a fire going at the Council Ring and enough marshmallows (and roasting stick) for all. Free and open to the public. Crossroads is a donor supported preserve welcoming learners of all ages to programs in science, history and the environment. The Collins Learning Center, located at 2041 Michigan in Sturgeon Bay, is open 2:00-4:30 and during scheduled activities.