Not so big giant galaxies

1) Not so big giant galaxies.

Dilemma:

In recent early galaxy surveys by JWST, it was viewed that not all galaxies of the early cosmos were small as anticipated. Data indicated thereat lay inexplicable huge galaxies among the early ones. How was this to be professionally explained when these huge galaxies challenge the Standard Model for galaxy sizes so soon after inception?

Resolutions langered in face of the data, even by CEERS ( Cosmic Evolution Early Release). The challenge was taken up by Katherine Chworowsky of U of Texas at Austin and Steve Finkelstein. Their work is submitted to "the Astrophysical Journal in Aug. 27, 2024.

So how do early galaxies appear from data to be extramassive? Magnification by lensing is one possibility. But how do these very distant galaxies appear so bright from that distance all the way to our detection?

"the galaxies that appear overly massive probably host  black holes rapidly consuming gas. Friction in the fast-moving gas emits heat and light, making these galaxies much brighter that they would be if that light emitted from stars."

"We are still seeing more galaxies than predicted", says Chworowsky.

"There are still about twice as many massive galaxies in Webb's data of the early universe as expected from the Standard Model."

2) The first stars may not have been uniformally massive as astronomers thought"

via Phys.Org, Aug. 25, by F. Grussie submitted to "Astronomy and Astrophysics"

"I am excited at the possibility that chemistry in the first 50 million to 100 million years after the Big Bang may have been more active than expected." So early stars had more time to form than has been assumed by the earlier activity. 

"One study, and independent laboratory experiment, demonstrates how molecular hydrogen-may have formed earlier and in larger abundances."