Far out cosmology: what our solar system moves into (Introduction)

by David Turell , Thursday, February 16, 2023, 18:46 (644 days ago) @ David Turell

We are moving from one region to another in the universe:

https://www.newscientist.com/article/2359129-were-hurtling-into-a-new-region-of-interst...

"Over the past decade or so, researchers like Bania have been showing that interstellar space is deeply fascinating. This so-called nothingness is brimming with exotic molecules, pulsating with radio waves and divided into gigantic bubbles, each with their own character. Now, as we are beginning to map out our place within the void more keenly, we are coming to see that this variety matters immensely – and that as the solar system heads towards a new region of interstellar space, there could be important ramifications for life on Earth.

"We are used to living in a thick soup of atmosphere. In a cubic centimetre of air, a volume the size of a six-sided dice, there are trillions of atoms. Gas, dust, water vapour, viruses, pollen and more all waft around. Just beyond our atmosphere, however, in interplanetary space, the conditions are close to a perfect vacuum. “Space is huge, and it’s mostly empty,” says Seth Redfield at Wesleyan University in Connecticut. Out there, the same volume contains, on average, just five atoms.

"This matter mostly consists of charged particles streaming out from the sun as the solar wind. We have known for decades about this flow of material and how it creates a protective zone around the solar system called the heliosphere. It cocoons us from high‑energy cosmic rays shooting at us from deep space – and a good thing too, because those rays can damage the cells and DNA in living things. Radiation levels are eight to 10 times higher outside this zone. “Without our heliosphere, would life even exist?” asks Jamie Rankin at Princeton University.

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"The discovery kick-started a new field, the study of molecules drifting in the interstellar medium. Bania is one of those who led the charge. “The big breakthrough in my lifetime was the whole discovery of molecules in interstellar space,” he says. As of 2022, some 256 types had been found, mostly identified from the way they absorb specific wavelengths of passing radio waves. “We found this rich molecular chemistry in space,” says Bania.

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"On a grander scale, our 10-light-year-wide Local Interstellar Cloud resides in a much larger, irregularly shaped structure called the Local Bubble, which is 1000 light years across. This is a giant shell of expanding gas formed by more than a dozen stars exploding as supernovae, with a density around a tenth that of the space outside the Local Bubble. Recent estimates have suggested that our solar system entered this bubble about 5 million years ago, and we are now roughly at its centre.

"In another 8 million years, it is predicted we will reach its edge. In 2022, Catherine Zucker at the Space Telescope Science Institute in Maryland and her colleagues used the European Space Agency’s Gaia telescope to track the motions and positions of stars in our vicinity. This showed that the centre of the Local Bubble is relatively empty, but that the edges have a much higher density of material. “We’re accidentally in a great position,” says Zucker. (my bold)

"Yet that could change as we near the edge. Ongoing work by Opher suggests the higher pressure we would experience as we near the edge of the Local Bubble would shrink the heliopause to the wrong side of Earth’s orbit, exposing us to far more cosmic rays. Earth would be “in interstellar space”, says Opher. It is reasonably well known that the sun will get much hotter over the next billion years, hot enough to boil Earth’s oceans away. But our traverse of interstellar space could have its own serious consequences for life on Earth far sooner. “Where we were in the past and where we are going to be in the future is critical,” says Opher. “I think it will have a direct effect on habitability.'” (my bold)

Comment: the universe is way more complex than we knew. Note my bolds. Accidental safe zone or God's designed protection?