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03/30/21 - The small and YOU seeing them - Stroking Data, Black Holes - Newly discovered sites

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Links for this week:

4 mins - STN member Dirk Bakker

Larry Dworsky's' latest Covid statistics:

virus file 47.pdf

STN member Susan Neubeck & Laurenn Rowland

Mexico says COVID-19 deaths likely 60% higher than confirmed tollMexico's death toll from the coronavirus pandemic is likely at least 60% higher than the confirmed number, putting it in excess of 300,000, according to government data.

STN member Laurenn Rowland

Pfizer, Moderna COVID-19 vaccines highly effective after first shot in real-world use, U.S. study showsCOVID-19 vaccines developed by Pfizer Inc with BioNTech SE and Moderna Inc reduced risk of infection by 80% two weeks or more after the first of two shots, according to data from a real-world U.S. study released on Monday.

7 mins - STN member Roger Lamont

9mins - STN member Roger Lamont

3 mins - STN member Roger Lamont

STN member Roger Lamont

An All-Sky X-Ray Survey Finds the Biggest Supernova Remnant Ever Seen - Universe TodayOur sky is missing supernovas. Stars live for millions or billions of years. But given the sheer number of stars in the Milky Way, we should still expect these cataclysmic stellar deaths every 30-50 years. Few of those explosions will be within naked-eye-range of Earth. Nova is from the Latin meaning “new”. Over the last … Continue reading "An All-Sky X-Ray Survey Finds the Biggest Supernova Remnant Ever Seen"

STN members Dirk Bakker & Roger Lamont

Astronomers’ Polarized Image Shows Magnetic Fields at the Edge of M87’s Black HoleNew image of M87 reveals how it looks in polarized light. MIT Haystack Observatory is one of the 13 stakeholder institutions that constitute the Event Horizon Telescope (EHT) collaboration, which produced the first-ever image of a black hole. The EHT revealed today a new view of the massive object

Stroking the Data...
https://youtu.be/xynvdOZdrcU?t=74

Disclaimer - Authors speculation M87

7 mins - STN member Roger Lamont

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17 mins - STN member Roger Lamont -Biggest Thing in the Universe:

12 mins - STN member Roger Lamont

STN member Roger Lamont

Wow! This incredible image of the Milky Way took 12 years to create

STN member Keith Johnson

4 mins - [clipped] Explanation

'Zombie' genes? Research shows some genes come to life in the brain after death: Post-mortem changes may shed light on important brain studiesResearchers analyzed gene expression in fresh brain tissue and found that gene expression in some cells actually increased after death.

3 mins - STN member Roger Lamont

Live updates: China unveils new discoveries from Sanxingdui

15 mins - STN member Roger Lamont

50 mins

7 mins - STN member Roger Lamont

Great Lakes people among first coppersmithsAbout 8500 years ago, hunter-gatherers living beside Eagle Lake in Wisconsin hammered out a conical, 10-centimeter-long projectile point made of pure copper. The finely crafted point, used to hunt big game, highlights a New World technological triumph—and a puzzle. A new study of that artifact and other traces of prehistoric mining concludes that what is known as the Old Copper Culture emerged, then mysteriously faded, far earlier than once thought. The dates show that early Native Americans were among the first people in the world to mine metal and fashion it into tools. They also suggest a regional climate shift might help explain why, after thousands of years, the pioneering metallurgists abruptly stopped making most copper tools and largely returned to stone and bone implements. Earth's largest and purest copper deposits are found around North America's Great Lakes. At some point, Native Americans learned to harvest the ore and heat, hammer, and grind it into tools. They left behind thousands of mines and countless copper artifacts, including lethal projectile points, hefty knives and axes, and petite fish hooks and awls. Today, it's not uncommon to meet residents of the region “who have buckets of copper artifacts [that they've found] tucked away in their basements,” says David Pompeani, a geologist at Kansas State University, Manhattan, who studies ancient mining. When researchers began to date the artifacts and mines, they saw a perplexing pattern: The dates suggested the people of the Old Copper Culture began to produce metal tools about 6000 years ago and then, for reasons that weren't clear, mostly abandoned copper implements about 3000 years ago. After that, early Native Americans used copper mostly for smaller, less utilitarian items associated with adornment, such as beads and bracelets. “The history is just so peculiar,” Pompeani says. In many other ancient cultures that learned how to make metal tools, the technology persisted, he says. About 10 years ago, Pompeani began doctoral research that cast doubt on the Old Copper timeline. He extracted sediment cores from lakes adjacent to prehistoric mines on Michigan's Keweenaw Peninsula and Isle Royale and measured trace metals in the cores, including lead and titanium, that had been released by processing the ore. The analyses showed copper mining began about 9500 years ago in some areas—some 3500 years earlier than once thought. It also ended earlier, about 5400 years ago, Pompeani reported in The Holocene in 2015. Now, a team led by Pompeani presents new evidence for the revised timeline. The researchers used modern methods to reanalyze 53 radiocarbon dates—including eight newly collected dates—associated with the Old Copper Culture. Some came from wood or cordage still attached to spearpoints; others came from charcoal, wood, or bone found at mines and human burials. The oldest reliably dated artifact turned out to be the 8500-year-old projectile point found in Wisconsin. This month in Radiocarbon , the team reports that the most reliable dates, combined with the sediment data, indicate the Old Copper Culture emerged at least 9500 years ago and peaked between 7000 and 5000 years ago. That makes it at least as old, and perhaps older, than copper-working cultures documented in the Middle East, where archaeologists have documented a copper pendant believed to be 8700 years old. The older window for Old Copper's peak doesn't surprise archaeologist Michelle Bebber of Kent State University who has studied the culture. The dates confirm “that hunter-gatherers [were] highly innovative,” she says, and willing to “regularly experiment with novel materials.” But why did the ancient copper experiment abruptly end? Bebber's work replicating Old Copper–style arrowheads, knives, and awls suggests they weren't necessarily superior to the alternatives, especially after factoring in the time and effort required to produce metal implements. In controlled laboratory tests, such as shooting arrows into clay blocks that simulate meat, she found that stone and bone implements were mostly just as effective as copper. That might be because Great Lakes copper is unusually pure, which makes it soft, unlike harder natural copper alloys found elsewhere in the world, she says. Only copper awls proved superior to bone hole punchers. Pompeani has identified another potential contributor to Old Copper's fade about 5000 years ago. Sediment cores, tree ring data, and other evidence suggest a sustained dry period struck the region around that time, he says. That could have fueled social and ecological disruptions that made it hard to devote time and resources to making copper tools. Over time, copper may have become something of a luxury item, used to signal social status. Copper awls, however, bucked this trend: They required relatively little ore to make, Bebber notes, and the people of the Great Lakes continued to use them for thousands of years.

Links from last Session

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SMA Science Book Club

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https://www.facebook.com/groups/scitechnature/

The SciTechNature get-together is also on Facebook.

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SMA Lifelong learning program

http://instituto-allende.edu.mx/en/lifelong-learning-program/

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...Because the acquisition of clean water in our town is not only a science, but a necessity, especially in the San Miguel de Allende area:

Caminos de Agua

https://caminosdeagua.org/en/home

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Caminos de Agua

https://caminosdeagua.org/en/home

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http://i3sma.org/

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SMA Rotary Club rests upon a foundation of compassion and science, so it too gets a heads up from SciTechNature.

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Best,

Stephen Goodfellow

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