- iridescent seaweed,
Origin of iridium
Examples from the Web for iridium
Two years later, a Russian satellite crashed into a communications satellite owned by the company Iridium.Space Station’s Near Miss Underlines the Dangers of Debris in Space|Eli Lake|March 27, 2012|DAILY BEAST
The latter metal, associated with platinum and iridium, has been found in South America.
What he wanted was the insurance and the ten million dollars' worth of iridium in the hold as well.The Space Rover|Edwin K. Sloat
Most of all he thought of Callisto and the iridium fields, which would mean much more tsith.One Purple Hope!|Henry Hasse
Note the quality of the following statements: Iridium has a power, purity and simplicity that pleases me; now I can make progress.
Therefore, it is preferred to every other metal (except, perhaps, iridium) for contact breakers.Electric Bells and All About Them|S. R. Bottone
Word Origin for iridium
1804, Modern Latin, coined by its discoverer, English chemist Smithson Tennant (1761-1815) from Greek iris (genitive iridos) "rainbow;" so called for "the striking variety of colours which it gives while dissolving in marine acid" [Tennant]
n. Symbol Ir
A Closer Look
In 1978 geologist Walter Alvarez discovered a high concentration of iridium in a layer of clay that had formed between the Mesozoic and Cenozoic eras, a period about 65 million years ago during which dinosaurs and many other organisms became extinct. This finding was significant as iridium is rare at Earth's surface (an unusually high concentration is called an iridium anomaly). Most surface iridium is thought to come from dust created when meteors disintegrate in the atmosphere or collide with Earth. Alvarez's father, the physicist Luis Alvarez, suggested that the iridium might have come from the impact of a meteor about 10 km (6.2 mi) across. Such an impact would have caused an enormous explosion, sending huge clouds of dust into the atmosphere. The dust, blocking out the Sun and causing extensive acid rain, would have triggered a worldwide ecological disaster. Many scientists think that such a disaster caused the extinction of the dinosaurs and at least 70 percent of all other species alive at the time, including most of Earth's land plants. Geologists have since found iridium deposits in rocks of a similar age in more than 100 places worldwide. Scientists in the early 1990s identified a large impact crater in the Yucatán peninsula of central Mexico that is the same age as the iridium deposit found by Alvarez. It is 200 km (125 mi) wide and may have been caused by the same impact.