[AnimalMuppet]

When this article talked about the ladder of standard candles, I started to wonder: when using the brightness of supernovae between near and far galaxies, what about intergalactic dust absorbing some of the light? Wouldn't that mess up the ability to just straighforwardly determine the distance from the brightness in a 1/r^2 way?

[scribu]

Yes, apparently that absorbtion of light by intergalactic dust is a well-known phenomenon called interstellar extinction.

There are various ways of accounting for it.

[roywiggins]

I am not an astronomer, but I imagine intergalactic dust leaves a distinct fingerprint on star spectra that you can measure.

Also, these numbers always have error bars. They spend a lot of time coming up with sources of error and characterizing them in order to understand the data fully.

[mountainboy]

now you're thinking rationally.

research "tired light". There are many competing theories.

Maybe read "Seeing Red" by Halton Arp, or anything by Tom Van Flandern. Or the book "Pushing Gravity". Or the electric universe guys, or subquantum kinetics, or modern mechanics, or plasma cosmology, or weber dynamics, or infinite universe, pretty much anything but the standard model actually.

be careful though, you might find yourself exposed to ideas that establishment status quo "science" tries hard to ignore.