Added 1 new A* page:A NASA recent article says that just a few days into conducting science operations, their new James Webb telescope has already been able to use its huge infrared-light-gathering mirrors to discover two galaxies thought to be among the oldest-known galaxies yet: if initial measurements are correct, the light Webb collected from them was emitted when the universe, now 13.8 billion years old, was a mere 450 and 350 million years old. They are labelled [1] and [2], respectively, in the image below:
Image by NASA, ESA, CSA, Tommaso Treu (UCLA), Zolt G. Levay (STScI): "Two of the farthest galaxies seen to date are captured in these Webb Space Telescope pictures of the outer regions of the giant galaxy cluster Abell 2744. The galaxies are not inside the cluster, but many billions of light-years farther behind it."
Although small—just "a few percent" of the Milky Way's dimensions—scientists were surprised to find these galaxies looking so smooth and orderly; it had been thought that galaxy formation would have started too late for them to be little more than chaotic blobs at this early point in the universe's life, but now the date for the birth of the first galaxies may have to be pushed back: "these galaxies would have had to have started coming together maybe just 100 million years after the big bang."
And despite their small scale, the galaxies are extremely bright. Scientists are tossing around a few theories to explain it: they could have lots of low-mass stars packed relatively tightly together or, more tantalizingly, they could contain "far fewer extraordinarily bright stars"; "long theorized, they would be the first stars ever born, blazing at blistering temperatures and made up only of primordial hydrogen and helium": "Population III" stars.
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The original 16" x 6.75" watercolor art for today's new A* page is up for auction on eBay. : )
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