RocketRon wrote:Has anyone suggested how old these dust clouds are,
or how they may have formed like that ?
They are young- probably no more than a few tens of millions of years. The structure of the nebula itself was broadly created by radiation from eta Carina, but that process largely stopped after that star erupted in 1841 producing a nebula blocking the intense UV that was the driving force in moving dust around. All the individual large clumps of dust that we observe are largely created by stellar feedback processes.
Has anyone estimated the actual likely tonnage of dust involved ?
The most recent number I've seen is 33,000 solar masses. About 1% of that mass is dust, the rest is atomic or molecular gas, mainly hydrogen. Individual clumps in the nebula range from a few solar masses to about 1000 solar masses.
How would such a tonnage be calculated ?
By applying the integrated intensity of infrared emissions to some basic equations related to emissivity.
Has anyone suggested what the dust may actually consist of ??
Yes, stardust, but what compositions would that likely involve....
Mainly carbon, silicon, and oxygen.