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Researchers Discover That Global Mass Extinctions of Land-Dwelling Animals Follow a 27-Million-Year Cycle
SciTechDaily ^ | December 10, 2020 | New York University

Posted on 12/11/2020 6:26:46 PM PST by BenLurkin

Sixty-six million years ago, 70 percent of all species on land and in the seas, including the dinosaurs, suddenly went extinct, in the disastrous aftermath of the collision of a large asteroid or comet with the Earth. Subsequently, paleontologists discovered that such mass extinctions of marine life, in which up to 90 percent of species disappeared, were not random events, but seemed to come in a 26-million-year cycle.

In their Historical Biology study, Rampino and co-authors Ken Caldeira of the Carnegie Institution for Science and Yuhong Zhu of NYU’s Center for Data Science, examined the record of mass extinctions of land-dwelling animals and concluded that they coincided with the extinctions of ocean life. They also performed new statistical analyses of the extinctions of land species and demonstrated that those events followed a similar cycle of about 27.5 million years.

What could be causing the periodic mass extinctions on land and in the seas? Mass extinctions are not the only events occurring in cycles: the ages of impact craters — created by asteroids and comets crashing to the Earth’s surface — also follow a cycle aligning with the extinction cycle.

Astrophysicists hypothesize that periodic comet showers occur in the Solar System every 26 to 30 million years, producing cyclical impacts and resulting in periodic mass extinctions. The Sun and planets cycle through the crowded mid-plane of the Milky Way Galaxy about every 30 million years. During those times, comet showers are possible, leading to large impacts on the Earth.

(Excerpt) Read more at scitechdaily.com ...


TOPICS: Miscellaneous
KEYWORDS: galacticplane; massextinctions
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To: Harmless Teddy Bear

41 posted on 12/11/2020 9:58:45 PM PST by CtBigPat (2020 is becoming everything 2012 aspired to be.)
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To: BenLurkin
Fortunately, we have someone here who was mucking about the last time one of these 27 million year thingies came along, and she can provide us with a lot of guidance and reassurance, as we pass through those same challenges again this time.


       

42 posted on 12/11/2020 10:12:20 PM PST by Songcraft
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To: ETL

always cheesecake for the guys, and the gals get the flabby old bearded men in the background...so not fair


43 posted on 12/11/2020 10:43:37 PM PST by blueplum ("...this moment is your moment: it belongs to you... " President Donald J. Trump, Jan 20, 2017) )
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To: ETL

Now you know why I was an archaeologist/paleontologist for a while. I really dug those ancient women, up!!


44 posted on 12/12/2020 12:29:27 AM PST by MadMax, the Grinning Reaper
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To: ETL

What really riled up the comets in the Ort Clout was when their production was stopped by Mercury manufacturers.
Hope I have the right car company, but the old Comet was actually a very nice looking car.


45 posted on 12/12/2020 12:32:26 AM PST by MadMax, the Grinning Reaper
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To: edwinland

I was going to say I read about this decades ago!


46 posted on 12/12/2020 2:12:54 AM PST by carcraft (Pray for our Country)
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To: ETL

Oort Cloud


47 posted on 12/12/2020 2:47:14 AM PST by Mr Information
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To: BenLurkin

The last mass extinction “science” has identified occurred 60 million years ago.

The researchers have no trouble admitting that while ignoring it ruins their 26/7-million year cycle theory.


48 posted on 12/12/2020 8:09:22 AM PST by Wuli
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To: CatOwner

Gods reset.


49 posted on 12/12/2020 8:28:02 AM PST by cp124 (Time for a new America.)
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To: edwinland

Stephen Jay Gould: my favorite science author.

“Punctuated Equilibrium,” right?


50 posted on 12/12/2020 8:37:32 AM PST by Chad N. Freud (FR is the modern equivalent of the Committees of Correspondence. Let other analogies arise.)
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To: meatloaf
To add to ‘the solar system is not standing still’..

it's 225 million mile ride at 250km/s that gives us roughly 8 points of extinction if the cycle is every 27million years.

Our galaxy has 4 major spiral arms and several minor arms with 'space' in between the arms. During our 225 million mile ride, we transverse these arms. Our Sun is currently transiting the minor Orion spiral arm. It takes about 10 million years to transit the arm. (That's also the lifetime of a ‘massive star’ formed and remaining within the arms, which eventually becomes a black hole or a supernova). The next two arms are Sagitarius, our next stop, and Perseus, about 100 million miles apart. If an extinction event is going to happen, it will likely happen in the Sagitarius arm or in 'open space' between the Orion and Sagitarius arms. While the sun is orbiting it's also 'bobbing' around the galaxy's mid-plane which takes about 70,000 years, or about 35,000 years above the plane and the same below.

A mathematician astrologer might be able to predict exactly where our solar system was on any given 10 million year increment, in which arm if any, whether the sun was below, above or on the midplane at the time of (a past or future predicted) extinction events. Just as astrologers predict where the stars were on a famous figure's birthday. Where was the earth 439, 364, 251, 214, and 65 million years ago in relation to where the earth is now? What external stresses of the space environment were the sun and earth subject to in each arm/interval between arms?

51 posted on 12/13/2020 4:52:06 PM PST by blueplum ("...this moment is your moment: it belongs to you... " President Donald J. Trump, Jan 20, 2017) )
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