by neufer » Wed Mar 02, 2016 10:21 pm
Tekija wrote:
Iridescent means rainbow-colored and derives from Iris, the Greek goddes that personifies the rainbow and is a messenger of Hera. "Among their deities, who dwelt on Mt. Olympus, was one called Iris. She was the special messenger of Hera, the Queen Goddess. When Iris carried special messages from Heaven to Earth, she used the rainbows as her pathway."
http://www.historiciris.org/articles/iris-legend.html
https://en.wikipedia.org/wiki/7_Iris wrote:
<<
7 Iris is a large main-belt asteroid orbiting the Sun between Mars and Jupiter. It is the fourth brightest object in the asteroid belt. It is classified as an S-type asteroid, meaning that it has a stony composition. Iris was discovered on August 13, 1847, by J. R. Hind from London. Iris was named after the rainbow goddess Iris in Greek mythology, who was a messenger to the gods, especially Hera. Her quality of attendant of Hera was particularly appropriate to the circumstances of discovery, as she was spotted following 3 Juno by less than an hour of right ascension (Juno is the Roman equivalent of Hera).>>
https://en.wikipedia.org/wiki/Iridium wrote:
<<Iridium is a chemical element with symbol Ir and atomic number
77. A very hard, brittle, silvery-white transition metal of the platinum group, iridium is generally credited with being the second densest element (after osmium) based on measured density, although calculations involving the space lattices of the elements show that iridium is denser. It is also the most corrosion-resistant metal, even at temperatures as high as 2000 °C. Although only certain molten salts and halogens are corrosive to solid iridium, finely divided iridium dust is much more reactive and can be flammable.
Iridium was discovered in 1803 among insoluble impurities in natural platinum. Smithson Tennant, the primary discoverer, named iridium for the Greek goddess Iris, personification of the rainbow, because of the striking and diverse colors of its salts. Iridium is one of the rarest elements in Earth's crust, with annual production and consumption of only three tonnes.
The Cretaceous–Paleogene boundary of 66 million years ago, marking the temporal border between the Cretaceous and Paleogene periods of geological time, was identified by a thin stratum of iridium-rich clay. A team led by Luis Alvarez proposed in 1980 an extraterrestrial origin for this iridium, attributing it to an asteroid or comet impact. Their theory, known as the Alvarez hypothesis, is now widely accepted to explain the extinction of the non-avian dinosaurs. A large buried impact crater structure with an estimated age of about 66 million years was later identified under what is now the Yucatán Peninsula (the Chicxulub crater).] Dewey M. McLean and others argue that the iridium may have been of volcanic origin instead, because Earth's core is rich in iridium, and active volcanoes such as Piton de la Fournaise, in the island of Réunion, are still releasing iridium.>>
[quote="Tekija"]
Iridescent means rainbow-colored and derives from Iris, the Greek goddes that personifies the rainbow and is a messenger of Hera. "Among their deities, who dwelt on Mt. Olympus, was one called Iris. She was the special messenger of Hera, the Queen Goddess. When Iris carried special messages from Heaven to Earth, she used the rainbows as her pathway."
[url]http://www.historiciris.org/articles/iris-legend.html[/url][/quote][quote=" https://en.wikipedia.org/wiki/7_Iris"]
<<[b][color=#0000FF][size=150]7[/size][/color][/b] Iris is a large main-belt asteroid orbiting the Sun between Mars and Jupiter. It is the fourth brightest object in the asteroid belt. It is classified as an S-type asteroid, meaning that it has a stony composition. Iris was discovered on August 13, 1847, by J. R. Hind from London. Iris was named after the rainbow goddess Iris in Greek mythology, who was a messenger to the gods, especially Hera. Her quality of attendant of Hera was particularly appropriate to the circumstances of discovery, as she was spotted following 3 Juno by less than an hour of right ascension (Juno is the Roman equivalent of Hera).>>[/quote][quote=" https://en.wikipedia.org/wiki/Iridium"]
<<Iridium is a chemical element with symbol Ir and atomic number [b][color=#0000FF][size=150]77[/size][/color][/b]. A very hard, brittle, silvery-white transition metal of the platinum group, iridium is generally credited with being the second densest element (after osmium) based on measured density, although calculations involving the space lattices of the elements show that iridium is denser. It is also the most corrosion-resistant metal, even at temperatures as high as 2000 °C. Although only certain molten salts and halogens are corrosive to solid iridium, finely divided iridium dust is much more reactive and can be flammable.
[float=right][img3="[b][color=#FF0000]The red arrow points to the Cretaceous–Paleogene boundary.[/color][/b]"]https://upload.wikimedia.org/wikipedia/commons/5/57/K-T_boundary.jpg[/img3][/float]
Iridium was discovered in 1803 among insoluble impurities in natural platinum. Smithson Tennant, the primary discoverer, named iridium for the Greek goddess Iris, personification of the rainbow, because of the striking and diverse colors of its salts. Iridium is one of the rarest elements in Earth's crust, with annual production and consumption of only three tonnes.
The Cretaceous–Paleogene boundary of 66 million years ago, marking the temporal border between the Cretaceous and Paleogene periods of geological time, was identified by a thin stratum of iridium-rich clay. A team led by Luis Alvarez proposed in 1980 an extraterrestrial origin for this iridium, attributing it to an asteroid or comet impact. Their theory, known as the Alvarez hypothesis, is now widely accepted to explain the extinction of the non-avian dinosaurs. A large buried impact crater structure with an estimated age of about 66 million years was later identified under what is now the Yucatán Peninsula (the Chicxulub crater).] Dewey M. McLean and others argue that the iridium may have been of volcanic origin instead, because Earth's core is rich in iridium, and active volcanoes such as Piton de la Fournaise, in the island of Réunion, are still releasing iridium.>>[/quote]