Launched on Christmas last year, the James Webb Space Telescope (or JWST for short) is a big fancy new space telescope that is the successor to the Hubble Space Telescope. The James Webb Space Telescope can see farther into distant space than any other telescope. Scientists believe that when a telescope like this looks at the farthest reaches of its limits, it is actually looking far back in time. That's because light travels at a speed of one light-year per year. So if a telescope such as the James Webb Space Telescope observes a very distant galaxy about 13 billion light-years away, that light should be the light the galaxy emitted 13 billion years ago.
A recent news story is entitled "SCIENTISTS PUZZLED BECAUSE JAMES WEBB IS SEEING STUFF THAT SHOULDN'T BE THERE." We read this:
"For a long time, for instance, scientists believed the universe's earliest, oldest galaxies to be small, slightly chaotic, and misshapen systems. But according to the Washington Post, JWST-captured imagery has revealed those galaxies to be shockingly massive, not to mention balanced and well-formed — a finding that challenges, and will likely rewrite, long-held understandings about the origins of our universe. 'The models just don't predict this,' Garth Illingworth, an astronomer at the University of California at Santa Cruz, told WaPo. 'How do you do this in the universe at such an early time? How do you form so many stars so quickly?' "
In the Washington Post article (which a paywall may prevent you from reading), we read this comment about observations of galaxies at very high redshifts, believed to be observations of galaxies appearing soon after the Big Bang:
"What has surprised astronomer Dan Coe of the Space Telescope Science Institute are the number of nicely shaped, disclike galaxies. 'We thought the early universe was this chaotic place where there's all these clumps of star formation, and things are all a jumble,' Coe said."
You can find the latest papers on this topic by going to the Cornell physics paper server, and using a search phrase of "JWST+high-redshift" or "JWST+earliest galaxies." Among the recent papers are these:
- The paper "A Long Time Ago in a Galaxy Far, Far Away: A Candidate z ~ 14 Galaxy in Early JWST CEERS Imaging" by dozens of different authors tells us this: "Should followup spectroscopy validate this redshift, our Universe was already aglow with fairly massive galaxies less than 300 Myr [million years] after the Big Bang." This contradicts what scientists have long told us, that such galaxies would take a billion years or longer to form.
- Another recent paper tells us, "Neither the high number of such objects found nor the high redshifts they reside at are expected from the previously favored predictions."
- Another paper reports the observation of "remarkably luminous" galaxies that already had a billion stars by the time the universe was only about 300 to 400 million years old.
- A very recent paper is entitled "On the stunning abundance of super-early, massive galaxies revealed by JWST." We read of the detection of "of two very bright" galaxies at "super-early epochs," with masses of at least a billion solar masses. We are told "this detection poses a serious challenge to essentially all models," and that what is observed deviates by some ten times from what is predicted. The authors resort to a "conspiracy theory" to explain these findings, telling us, "The weak evolution from z = 7 to z ≈ 14 of the LF bright end arises from the conspiracy between a decreasing dust attenuation, making galaxies brighter, that almost exactly compensates for the increasing shortage of their host halos."
- A very recent paper tells us, "The James Webb Space Telescope (JWST) has discovered a surprising abundance of bright galaxy candidates in the very early Universe (<500Myrs after the Big Bang), calling into question current galaxy formation models."
- Another recent paper is entitled "Schrodinger's Galaxy Candidate: Puzzlingly Luminous at z≈17, or Dusty/Quenched at z≈5?" The paper mentions a galaxy that seems to have about 5 billion stars, observed at a time when the universe was only about 200 million years old, noting that this "challenges virtually every early galaxy evolution model." The authors also resort to a "conspiracy theory" to try to explain this embarrassing finding, using the word "conspire" in their abstract.
- Another recent paper notes that "early observations with JWST have led to the discovery of an unexpected large density...of massive galaxies... at extremely high redshifts z ≈ 10, " and finds in its Section 7 that the most-popular model of cosmology (called lambda cold dark matter or LCDM) is "excluded" (in other words, ruled out) at a moderately strong two-sigma level by the latest observations.
- Another recent paper entitled "A very early onset of massive galaxy formation" refers to high redshift galaxies (believed to be the earliest galaxies formed), and notes that "the mass density in the most massive galaxies exceeds the total previously-estimated mass density... by a factor of ∼ 2 at z ∼ 8 and by two orders of magnitude at z ∼ 10." This being wrong by two orders of magnitude refers to predictions being wrong by a factor of about 100 times.
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