NASA, ESA, J. Hester, A. Loll (ASU) Posted on 11/16/2020 7:22:17 AM PST by Red Badger
NASA, ESA, J. Hester, A. Loll (ASU)
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Supernovas may have affected the Earth’s climate in the last 40,000 years.
Tree-ring data suggests supernovas caused spikes in radiocarbon.
Could the next nearby supernova cause a collapse of civilization?
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Dendrochronology is a fancy word for tree-ring dating, where the age of a tree can be determined by the number of growth rings across its trunk. But there’s a lot more to learn from looking at a tree’s rings than simply its age.
Like fingerprints, tree rings give scientists clues to what the world was like when a tree was alive. By studying tree rings, we can determine when the tree lived, the climatic conditions through which it lived, and possibly, what was happening in the universe at the time.
In a new study published in the International Journal of Astrobiology, geoscientist Robert Brakenridge, of the University of Colorado, suggests a number of supernovas may have left their mark on life on Earth over the last 40,000 years. By poring through countless tree ring records and matching them to known supernova events, Brakenridge discovered that of the eight recent supernovas he studied, each one seemed to leave their mark on trees.
The alarming part? Four of those supernovas may have significantly disrupted Earth’s climate, leading scientists to wonder what the next supernova event might mean for civilization.
Supernovas are brilliant explosions caused by the deaths of massive stars. They’re the most massive and energetic explosions known to science, sometimes shining brighter than the combined light of their galaxies. The overwhelming energy released in such an explosion has caused scientists to worry that a nearby supernova could wipe away life on Earth. But even distant supernovas could pose a risk by damaging Earth’s protective ozone layer, Brakenridge said in a press release.
“These are extreme events, and their potential effects seem to match tree ring records," he said.
Brakenridge’s research relies on the scientific art of radiocarbon dating. When carbon atoms in Earth’s atmosphere get struck by cosmic rays from space, they can form a radioactive isotope called carbon-14, or radiocarbon. Some of those carbon isotopes get taken in by plants and animals, leaving a lasting fingerprint that scientists use to date their remains.
When dendrochronologists look at the amount of radiocarbon in tree rings, they expect a steady decline in the isotope as they look at older rings. To their surprise, scientists have discovered a number of cases where the concentration of radiocarbon in tree rings spike. Without any earthly explanations, scientists have looked toward the cosmos for answers.
Many scientists believe these spikes may be caused by solar activity. Violent solar flares can cause the ejection of plasmas and solar particles that bombard Earth’s upper atmosphere and may explain the spikes in radiocarbon. But a handful of scientists believe the answer lives farther out, beyond the comforts of our solar system.
“We’re seeing terrestrial events that are begging for an explanation,” Brakenridge said. “There are really only two possibilities: A solar flare or a supernova. I think the supernova hypothesis has been dismissed too quickly.”
To dig deeper, Brakenridge created a list of recorded supernovas that occurred near Earth over the last 40,000 years. When he compared these records to the carbon fingerprints left in tree rings, eight of the closest matching supernova events coincided with spikes in radiocarbon.
The last time scientists observed a supernova with the naked eye was in 1604, when Johannes Kepler described SN 1604 (Kepler’s Supernova) in De Stella Nova. And the earliest account of a supernova, some believe, is a stone carving in Burzaham, India. The artwork, estimated to be between 4,000 and 6,000 years old, depicts a hunting scene where two people hunt under a sky with two suggestively bright celestial objects. Some researchers think this may represent a supernova estimated to be as bright as the moon that occurred during the same time period.
VIDEO AT LINK.........................
Astronomers are able to record these past explosions by observing the colorful nebulas they leave behind and estimate when they occurred. However, this method of dating supernovas isn’t an exact science, and estimates can be off by as much as 1,500 years.
This goes to show that when looking at some historical records, scientists rarely can be certain. We may not know the real danger a nearby supernova poses to civilization until it happens. Let’s just hope that doesn’t take place for a very, very long time.
Does the actions of a butterfly on another planet lead to a chain of events that cause climate change on earth? (from the “science” that says everything affects everything in some way).
The oldest trees are about 2,500 years old. The tree ring research was begun in the twenties and thirties in Tucson at the UofA. One display slice is about 12 feet in diameter. I remember seeing it as a child and that experience left me with the belief that extrememe global changes have occurred naturally way before climate scare.
Where did he get a 40,000 year old tree?
Only if it's Mothra!................
Our sun can have corona storms that resemble novas, some call micro novas. These are a bigger threat.
“It’s all those aliens driving Super Novas........... “
Once you go Nova, you never go back.
You go on a Ventura.....................
This books makes a very good case for solar system & galactic radiation events effective climate.
Humans had nothing to do with it!
That’s why I’m a Mustang guy.
There is a cure for that LOL.
Bow tie until you die MoPar or no car
I have owned all three. I have had a Camaro, Firebird and a Charger.....................
No! No! It’s capitalism that causes climate change.
Where did he get a 40,000 year old tree?
I asked the same question a while back and then learned how the research works for 'Dendrochronology' and it is quite ingenious.
Take a long-lived modern tree recently cored (core sample taken from living tree) or cut down. Examine the tree rings that reflect each year's growth and thus the corresponding growing conditions for that locality. Let us say that the tree is 300 years old, so you see a record of wide rings for good grow years and narrow for bad ones.
Now find the record of an OLD local tree from 250 years back, which is nowhere as impossible as it may sound. As an example, the "Bald Cypress Tree" of the Southeast USofA can live between 600 and 1,000 years. Additionally, even dead trees resist falling and when they do fall in the swamps, they can resist rot under the right conditions.
So you then match the current tree's rings at 250 years ago to one that was 600 years old THEN and now you are back 850 years. Repeat as possible and while the 'local' variable almost always has to expand, these tree 'records' are constantly being added to worldwide. An amazing resource for a study method that dates back to Europe in the mid-1700s. For North America, there is sufficient matches to go back to 10,000 BCE but NOT, obviously, for a single local area.
However, for research like this study of Supernovae (SN) effects, it matters little about the locality or continuity. So for older tree rings, the dating of the tree samples can be by isotopic O2 measurements matched to Greenland (& other) ice core samples. Also usable are catastrophic volcano eruptions that produce extremely small tree rings due to sunlight blockage. Thus you can get a good estimate of a tree's life dates from several cross-checks. Then looking at that tree's rings for a suspect year of a SN can be a data point of effects.
The stars are so far away, that their light has not gotten here yet..............
That's why I wear my sunglasses at night. You never know when it will all arrive.
Cory Hart, izzat you?...................
Same Firebird 68 Nova 69 Mustang 65 many of the tri fives miss the the most.
bracket racer for five years miss that the most but it came down to $$$$$$$$$$$ it’s a rich mans game now.
Look up “consistent” and “varying” and get back to me.
“Where did he get a 40,000 year old tree?”
There are lots of places to get old trees, although 40,000 years is probably pretty far back for that. On the other hand, they do find perfectly preserved mammoths and cave bears from sudden-onset ice ages. They get the trees from low oxygen environments like stagnant water bodies and peat bogs.
There was a study I read once about tree rings from submerged trees that were thousands of years old. I don’t recall the location, maybe Scandinavia, but they carbon dated each individual ring and found that some years the C-14 levels in the environment were multiple times the normal levels. If you didn’t know to look for that, a lot of artifacts would seem much younger than they actually were. It was quite an interesting study.
Are you questioning science?
So does that mean that it’s not settled science?
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