Astronomers discover thousands of active red galaxy hearts with powerful radio signals

[Admin]

The radio signals hint at an important evolutionary step in the lives of galaxies.

Astronomers discover thousands of active red galaxy hearts with powerful radio signals : Read more

 

[rod]

"Therefore, when astronomers see a red quasar, they are seeing a younger quasar than if they were to see a blue one."

My note, interesting difference between seeing red stars on the H-R diagram and blue stars. Some notes from the paper cited.

A striking relationship between dust extinction and radio detection in DESI QSOs: evidence for a dusty blow-out phase in red QSOs, https://academic.oup.com/mnras/article/525/4/5575/7273139?login=false

"...in this paper, we use AB magnitudes. Throughout our work, we adopt a flat λ-cosmology with H0 = 70 km s^−1 Mpc^−1, ΩM=0.3 and Ωλ = 0.7. The data underlying the figures in this paper are available online: https://doi.org/10.5281/zenodo.8147342.

I note the redshifts fall around 2.5. "From visually inspecting our DESI SP sample, we found that ∼89 per cent (2700/3038) of the DESI spectra have high quality (VI quality ≥ 2.5) redshifts and spectypes."

Using Ned Wright calculator, "The age at redshift z was 2.646 Gyr." "The light travel time was 11.076 Gyr."

"The comoving radial distance, which goes into Hubble's law, is 5938.5 Mpc or 19.369 Gly."

At 19.369 Gly from Earth, space is expanding faster than c velocity.

 

[rod]

As space.com states, "A fraction of red quasars have been shown to be young active galaxies smothered in cosmic dust." The dust is not the postulated pristine, metal free gas created during BBN and filling the universe during the postulated cosmic dark ages, well before Population III stars are said to evolve. Even out to distances of some 11 billion light-years from Earth.