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View Full Version : There's A lot of Dust Out There in the Universe



Fraser
2008-May-19, 02:30 PM
The whole point of putting telescopes in orbit is to avoid distortions caused by our murky atmosphere. But now astronomers say they have calculated only half the light of our universe reaches telescopes even those in orbit because of the amount of dust that permeates the universe. In essence, they say, [...]

More... (http://www.universetoday.com/2008/05/19/theres-a-lot-of-dust-out-there-in-the-universe/)

Nick Theodorakis
2008-May-19, 03:20 PM
It's all those darned Dyson spheres getting in the way...

Nick

trinitree88
2008-May-20, 12:37 PM
The whole point of putting telescopes in orbit is to avoid distortions caused by our murky atmosphere. But now astronomers say they have calculated only half the light of our universe reaches telescopes even those in orbit because of the amount of dust that permeates the universe. In essence, they say, [...]

More... (http://www.universetoday.com/2008/05/19/theres-a-lot-of-dust-out-there-in-the-universe/)

Fraser. That would seem to have an effect on the Tully-Fisher relationship that calibrates galaxy rotation rates with their intrinsic luminosities. If so, that's one of the Standard Candle stepping stones to the universe's diameter....and it's imputed expansion rate, No? pete:think:

see:http://zebu.uoregon.edu/~imamura/209/apr7/TF.html

kammueller
2008-May-21, 12:36 AM
What does this discovery say about the expansion rate of the universe? If we are using standard candles based on luminosity of type 1 supernovaes, then if we assume there is more dust the further from us you get, and it would seem logical that more distant opbjects would look dimmer than expected.

Mathematically how do we wrap this discovery into this data and see what effect it has on the outcome. Does it reign back the expansion and perhaps put a cabosh on Dark Energy, or is it just an insignificant adjustment.

I haven't seen anything posted yet, so I am wondering if anyone has any answers for this......Or is it going to take some time to get a handle on this?

Kwalish Kid
2008-May-24, 08:37 PM
Is there any critical response to this finding yet?

Jerry
2008-Sep-01, 07:33 PM
Is there any critical response to this finding yet?

...Still waiting.

There is a slew of papers in archives the last week discussing interstellar dust and such

http://xxx.lanl.gov/abs/0808.4129 (and several other papers -from 0808.413 - more posted on other days)

I haven't even perused them all, but none seem to address this issue directly. There is an interesting conflict in the dust ratios calculated using gamma rays, as compared to quasar MgII lines. http://xxx.lanl.gov/PS_cache/arxiv/pdf/0808/0808.4157v1.pdf (This discrepancy is consistent with some intrinsic redshifting in quasar galaxy spectra.) See also arXiv:0808.4115 [ps, pdf, other]
Title: On Dust Extinction of Gamma-ray Burst Host Galaxies

There have to be a LOT of red faces out there: Much greater dust attenuation than prior analysis suggests is a killer cosmic conclusion.

trinitree88
2008-Sep-02, 12:12 PM
Interesting. That would mean that the interstellar reddening attributable to velocity has a larger component due to dust scattering than previously thought...even above and beyond this:http://astro.elte.hu/astro/en/library/padeu/padeu_vol_17/padeu_vol17_sipos_etal.pdf

As the reddening of distant type 1a's is all about the acceleration of the universe...somebody is putting on the brakes, here. pete