Visible-light astronomy Visible-light astronomy Visible-light astronomy encompasses a wide variety of observations via telescopes that are sensitive in the range of visible light (optical telescopes). Visible-light astronomy is part of optical astronomy, and differs from astronomies based on invisible types of light in the electromagnetic radiation spectrum, such as radio waves, infrared waves, ultraviolet waves, X-ray waves and gamma-ray waves. Visible light ranges from 380 to 750 nanometers in wavelength. Visible-light astronomy has existed as long as people have been looking up at the night sky, although it has since improved in its observational capabilities since the invention of the telescope, which
Ultraviolet communication in butterflies the pterins absorb the ultraviolet light. Thus, butterflies are able to reflect ultraviolet light as a result of the organization and composition of their wing scales resulting in thin layer constructive interference and can absorb ultraviolet through the action of pterin pigments. Butterflies receive ultraviolet signals by utilizing a special photoreceptor pigment in the butterfly eye. The butterfly eye is similar to the average insect eye in that it is composed of numerous ommatidia. Each butterfly ommatidium contains nine photoreceptors with generally each photoreceptor utilizing a single visual pigment. A UV sensitive visual pigment is responsible for a butterfly’s ability