What’s more, the same eighth cell not only manipulates circularly polarised light, but it can sense ultraviolet light too. Its eyes work across the entire visible spectrum, from ultraviolet to infrared, achieving a level of performance that our technology can’t compete with. But the mantis shrimp has already done it. If you change the wavelength slightly, they become ineffective, so designing a wave plate that works for many colours is exceptionally difficult. Synthetic wave plates only work well for one colour of light. Similar devices are also found in camera filters, CD players and DVD players but these man-made versions are far inferior to the mantis shrimp’s biological tech. In technical terms, the eighth cell is a “quarter-wave plate”, because it rotates the plane in which light vibrates. It’s this cell that converts circularly polarised light into its linear version. The eighth cell sits on top and its slit is angled at 45 degrees to the seven below it. Seven sit in a cylinder and each has a tiny slit that polarised light can pass through if it’s vibrating in the right plane. Each eye is packed with light-sensitive cells called rhabdoms that are arranged in groups of eight. To date, they are still the only animal that can see these spiralling beams of light. Last year, scientists discovered that they can also see circularly polarised light, which travels in the shape of a helix. ![]() Think of attaching a piece of string to a wall and shaking it up and down, and you’ll get the idea. ![]() Previous studies have found that mantis shrimps can detect polarised light – light that vibrates in a single plane as it travels. If this biological design can be synthesised, it could form the basis of tomorrow’s multimedia players and hard drives. It contains a technology that’s very similar to that found in CD and DVD players, but it completely outclasses our man-made efforts. They can even see a special type of light – ‘circularly polarised light’ – that no other animal can.īut Nicholas Roberts from the University of Bristol has found a new twist to the mantis shrimp’s eye. While we see in three colours, they see in twelve, and they can tune individual light-sensitive cells depending on local light levels. ![]() Each eye can move independently and can focus on object with three different areas, giving the mantis shrimp “trinocular vision”. Practical advice throughout helps readers see what they have been reading about, building key observational skills such as “star hopping” from easy-to-find stars to fainter deep-sky objects and focusing on “deep sky treasures:” areas rich in observable phenomena.Īpproachable and authoritative, gorgeous and fascinating, National Geographic Stargazer’s Atlas will intrigue all who love to gaze up in wonder at the night sky-and find themselves wanting to know more.The most incredible eyes in the animal world can be found under the sea, on the head of the mantis shrimps. Richly illustrated with awe-inspiring imagery-including photos from space missions and telescopes, science-based artists’ interpretations, and explanatory graphics-the book also contains 170 maps and charts of planets, moons, and constellations, from Earth’s moon to moons of Saturn. A unique chapter on astrotourism highlights ancient observatories, dark-sky preserves, and other global destinations for the sky-seeking traveler a final chapter details current and future space missions and what they might discover. Richly illustrated with luminous photographs and informative maps and graphics, this expansive book is the perfect guide for everyone discovering the wonders of the night sky, from those just learning the constellations to dedicated telescope observers.Ĭombining science, exploration, and storytelling, National Geographic Stargazer’s Atlas invites readers to roam the night sky for constellations, planets and moons, eclipses, comets and meteor showers, auroras, and deep-sky treasures including nebulae and galaxies-many visible to the naked eye and all with binoculars or a backyard telescope.īeginning with basic space science and including a complete set of night sky maps for all four seasons in the Northern and Southern Hemispheres, this fascinating book guides the reader toward the most rewarding observations.
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