Electrons in cryptochrome usually come in pairs, each with an opposite spin like a planet revolving on its axis. But when light strikes the molecule, it can carry one of the electrons away. The presence of a magnetic field can then make each spinning electron wobble like a plate balanced on a stick. When the wayward electron returns to its original molecule, any change it has picked up in its spin sparks a chemical signal that some scientists believe allows birds to see magnetic fields as a pattern of colors.
...E atenção, Alentejo, Cabo Verde, e Nordeste do Brasil, Cientistas Suíços conseguiram criar núvens com um Laser!
Geneva, Switzerland--Swiss scientists from the University of Geneva have used a laser both in the lab and in the skies over Berlin, Germany to create clouds, according to a May 2 story in New Scientist from Colin Barras at http://www.newscientist.com/article/dn18848-laser-creates-clouds-over-germany.html?DCMP=OTC-rss&nsref=online-news.
Barras explains that people have experimented with cloud seeding for decades in the hope of boosting rainfall, usually by sprinkling silver iodide crystals into clouds high in the atmosphere. These crystals encourage large water droplets to form around them, and the droplets then fall as rain--in theory, at least. "The efficiency of this technique is controversial," says Jerome Kasparian at the University of Geneva, one member of a research team that think lasers may be a better way to trigger rain on demand.
In the lab the team fired extremely short pulses of infrared laser light into a chamber of water-saturated air at -24°C. Linear clouds could be seen to form in the laser's wake, like a miniature airplane contrail. Kasparian says that the laser pulses generate clouds by stripping electrons from atoms in air, which encourage the formation of hydroxyl radicals. Those convert sulphur and nitrogen dioxides in air into particles that act as seeds to grow water droplets.