In this activity, museum visitors will be exposed to the term ‘Photonic Crystals’. They will see and explore some of the well-known photonic crystals in nature and will also be able observe one method that scientists use in trying to replicate this process.
Changing Colors is an interactive exhibit that shows how some high-tech nanomaterials mimic natural phenomena. Super-small, light-reflecting structures—instead of pigments—on the wings of some butterflies create intense, iridescent colors. Nanoscientists have replicated this effect with layered, super-thin films. Watch the colors change on butterfly wings and thin-film slides as you move them beneath a light source, and discover how nanoscale structures can manipulate light and create color. Butterfly specimens deteriorate with heavy use, and may need to be replaced periodically.
The colors of the Blue Morpho's wing are generated by nanometer-sized structures on the wing's scales. In this image, light reflected from the scales creates the Morpho's characteristic iridescent blue color.
The colors of the Blue Morpho's wing are generated by nanometer-sized structures on the wing's scales. In this image, only the light passing through the wing is seen, revealing the wing's pigment-produced brown hue.
This scanning electron microscope image shows ridges on a Blue Morpho Butterfly wing scale. These ridges contain nanoscale structures that reflect light to create the Morpho's iridescent colors.
The overlapping scales on the wing of the Blue Morpho Butterfly contain nanoscale structures that reflect light to create iridescent colors. This scanning electron microscope image shows Morpho wing scales from above.
The iridescent colors of the Blue Morpho Butterfly's wings are produced by nanostructures that reflect different wavelengths of light.
The Blue Morpho is common in Central and South America and known for its bright blue wings. However, these iridescent colors are created not by pigments in the wing tissues but instead by the way light interacts with nanometer-sized structures on the Morpho's wing scales. This effect is being studied as a model in the development of new fabrics, dye-free paints, and anti-counterfeit technologies for currency.
The tree-like structures in this scanning electron microscope image of a cross section of a butterfly wing are on the undersides of the Morpho's wing scale ridges. These microribs reflect light to create iridescent colors.
In this hands-on activity, visitors explore the structure of seashells and learn that seashells are a composite material made of both inorganic and organic materials. Visitors compare the mechanical properties of plaster bricks and dried sheets of glue, which helps them discover that both toughness and hardness are important mechanical properties. To see what a shell would be like if it were not so tough, visitors try to break normal shells and shells that have been either baked or soaked in bleach.
Mr. O talks about iridescence and Blue Morpho butterflies in another "O Wow" moment at the Children's Museum of Houston.