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.
Where did he get a 40,000 year old tree?
OK. So they are trying to explain away warmth in the past when only cars and cow farts cause warming. Science you know.
A fun question that most don’t even think about: If every point in the entire sky contains, at some distance, a star who’s light energy is reaching earth, why is the sky not lit up like daylight even at night? There is an answer, but most people don’t even ask the question.
A supernova within about 150 light years from Earth would severely impact the planet. For that matter a gamma ray burst thousands of light years away would to the same if aimed at Earth. And we thought that asteroids were all we had to worry about. Lol.
"Far-Off Supernovas Caused Climate Change on Earth"
Our climate has always changed. It's never been static.
Time to send out a petition to Dem voters stating we need to dedicate our resources to stop all Supernovas
That question was answered by Edgar Allen Poe, who was not only a great story teller, but also an amateur astronomer.
The stars are so far away, that their light has not gotten here yet..............
It's all those aliens driving Super Novas...........
SuspiciousObservers.org gives a daily six minute presentation of space weather predictions and how it affects our planet.
Warning, big words:)
That’s only one of the theories to explain Olber’s paradox. :)
https://en.wikipedia.org/wiki/Olbers%27_paradox
Don’t get me wrong. It might be true, but it is really more of a hypothesis than a theory until they can come up with a good way to test it.
Good one
Another reason is, that ‘space’ is so clean that the light from distant stars is not ‘scattered’ like in our own atmosphere....................
Look up dendrochronology, it’s mostly not about living trees.
That’s why I’m a Mustang guy. Gotta save de Erf.................
A distant star can change our climate, but the closest one has no effect on our climate?
Got it.
Well, when it goes nova, it will..................
Warning, big words:)
Worse, big words with consistent interpretations that actually match the available data.
You mean... Worse, big words with varying interpretations that actually match the constantly changing available data.
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