External accretion of extraterrestrial mass is irrefutable. Everyone knows about meteors and meteor showers that regularly enhance the night skies at certain times each year. Meteorites, the solid remnants of meteors that land on Earth, are also known to almost everyone, even though few may have actually seen one.
(SOURCE)Retrieved by Pat Darnell
When we GooGle: Accretion Dust, Disk
We get -- Reference: [HERE]
W. K. M. Rice, Philip J. Armitage, Kenneth Wood, and G. Lodato, Monthly Notices of the Royal Astronomical Society, 373 1619-1926 (2006).
When astronomers observe a star surrounded by an accretion disk in visible light, they typically see radiation from the star at the center of the disk. When they observe the disk in the infrared, they typically see emission at a continuous range of wavelengths, ranging from short to long. The short-wavelength IR radiation emanates from dust closest to the star. There the dust is heated to temperatures of a 1000 °C or more. Dust in the disk farther away from the star is cooler and emits at longer IR wavelengths.
The problem is it's virtually impossible to actually see a nascent planet inside a swirling, turbulent, and opaque disk of gas and dust. It's much easier to identify planets orbiting stars a billion years old (or older) whose accretion disks have vanished.
Not ones to throw up their hands in despair, however, Fellow Phil Armitage and colleagues from the University of Edinburgh, the University of St. Andrews, and Cambridge's Institute of Astronomy recently analyzed some indirect evidence that some accretion disks may have at least one Jupiter-sized gas planet within them. The evidence comes from the properties of the disk itself. (Read Article HERE)
Today's Post: More in MooPig's Query:
"What's a Billion anyway amongst Friends?" while listening to Lenny Breau's "Mercy, Mercy, Mercy..." click to hear for yo'seff... what do you suppose dust accretion sounds like on a cosmic disk?
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