Cosmology: Milky Way North and South giant bubbles (Introduction)

by David Turell , Wednesday, January 06, 2021, 23:41 (1416 days ago) @ David Turell

These are gamma ray and x-ray bubbles:

https://www.quantamagazine.org/space-telescope-shows-galaxy-size-bubbles-over-the-milky...

"He published simulations in 1977 that produced digital clouds lining up with the spur, and ever since then he has told anyone who would listen that the spur actually hovers tens of thousands of light-years above the disk. He described it as an expanding shock wave from a galactic calamity dating back millions of years.

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"Then in 2010, the Fermi space telescope caught the faint gamma-ray glow of two humungous lobes, each extending roughly 20,000 light-years from the galaxy’s center. They were too small to trace the North Polar Spur, but they otherwise looked just like the galactic-scale clouds of hot gas Sofue predicted. Astronomers began to wonder: If the galaxy had at least one pair of bubbles, perhaps the spur was part of a second set?

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"The new images have further cemented the change of opinion. They came from eROSITA, an orbiting X-ray telescope that launched in 2019 to track dark energy’s effect on galaxy clusters. The eROSITA team released a preliminary map in June, the fruit of the telescope’s first six months of observations.

"The map traces X-ray bubbles that stand an estimated 45,000 light-years tall, engulfing the gamma-ray Fermi bubbles. Their X-rays shine from gas that measures 3 million to 4 million degrees Kelvin as it expands outward at 300 to 400 kilometers per second. And not only does the northern bubble align perfectly with the spur, its mirror image is obvious as well, just as Sofue predicted. “I was particularly happy to see the southern bubble clearly exhibited, so similar to my simulation,” he said.

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"But the meaning of eROSITA’s mushroom clouds is clear: Something went bang in the center of the Milky Way around 15 million to 20 million years ago, around the same time hyenas and weasels were emerging on Earth.

“I think now [the debate] is done, more or less,” said Predehl, who spent 25 years developing eROSITA.

"What exploded? Based on the energy required to make the clouds so big and so hot, there are two plausible sources.

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"The ... culprit is the supermassive black hole that sits at the galaxy’s heart. The 4-million-solar-mass leviathan is relatively quiet today. But if a large cloud of gas once strayed too close, the black hole could have switched on like a spotlight. While feasting on the hapless passerby, the black hole would have gobbled down half the cloud while energy from the other half sprayed out above and below the disk, inflating the X-ray bubbles and perhaps the Fermi bubbles too (although the two pairs could also represent separate episodes of activity, Predehl noted).

"Astronomers have long observed other galaxies that shoot out jets above and below their disks, and they’ve wondered what makes the central supermassive black holes in those galaxies churn so much more violently than ours does. The Fermi bubbles, and now the eROSITA bubbles, suggest that the main difference may simply be the passage of time."

Comment: It all gets complexer and complexer and God has not explained why all the weirdness. But is always tums out the weird is necessary, and makes us agree God knows what He is doing and how everything we see must be necessarily designed for creation.