|Via Lattea img adatt. da SM|
È possibile che esista una relazione diretta tra le estinzioni di massa, la caduta di comete e gli sconvolgimenti geologici che si sono verificati sulla Terra nel corso del tempo e il passaggio ciclico, ogni 30-40 milioni di anni, del Sistema Solare attraverso il piano della Via Lattea e lo strato di materia oscura che esso contiene. A suggerirlo è il biologo statunitense Michael Rampino in un articolo pubblicato sul giornale scientifico Monthly Notices of The Royal Astronomical Society.
Clicca qui sotto per ascoltare il podcast in italiano
Nota di Gian Gianni Gnè
Mi si consenta di sottolineare che la "Materia Oscura" di cui tanto si blabbleggia in questo podcast a dir poco ridicolo per quanto è superficale nella trattazione dell'argomento, ecco, dicevo, mi si consenta almeno di precisare che la suddetta "Materia Oscura" di cui si parla nel suddetto podcast (e quindi nell'articolo di riferimento) è ritenuta essere fatta di WIMPs, e non di MACHOs. Per una trattazione finalmente professionale della faccenda "Materia Oscura" e delle sue declinazioni WIMPs e MACHOs si veda qui e qui.
THE EARTH, THE DARK MATTER AND THE GALACTIC TRIP TOWARD MASS EXTINCTION
|Milky Way img adpt. by SM|
A direct link can exist among catastrophic geologic events, comet impacts, mass extinctions and the Earth crossing, every 30-40 million years, the Milky Way’s mid-plane and its clumps of dark matter. The hypothesis is discussed by the American biologist Michael Rampino in a paper published in the journal Monthly Notices of The Royal Astronomical Society.
Listen to the podcast in Eng?ish here
or here (Podcast Machine)
The following text is that of the podcast
O-oooooh hallo dear English-hearing-speaking-thinking listener welcome to the second of my podcast in Engmark, that is "English-question mark" (i.e. Eng?ish), a language that is to proper English what a three tons mean black rhino is to a fluffy puffy little puppy. Well, or vice versa.
The voice you’re hearing is that of my avatar, a dumb human controlled via a wireless-voodoo trick by me, “sciencemug”, the blog which tells you about science, distracts the monster under your bed luring it with a box of donuts inside a box of tacos inside a box of bacon inside a box of pizza aaand which dances the steps of light and breeze with the demons in your head so you can have a full night of good solid sleep (unlike the monster under your bed that, in the meanwhile, given all the stuff it gulped down, will be spending the whole night painfully barfing in its bathroom, which, by the way, is right under your bathroom).
Sooo, where were we at? Ah, yeah, right, podcast in Engmark, black rhino, avatar, I am sciencemug the blog… What else? Oh right! The topic of today’s podcast! Well, dear listener, here it comes!
Today I’ll tell you a story about Earth, dark matter, and a cosmic travel toward mass extinction… Uuuuuh, spooky!
A direct link can exist among catastrophic geologic events, comet impacts, mass extinctions and the Earth crossing, every 30-40 million years, the Milky Way’s mid-plane and its clumps of dark matter. Professor Michael Rampino, a biologist of the NY University who collaborates with NASA, finds this possible link after analyzing data from studies of the last 30 years in the fields of astronomy, geology and biology. Professor Rampino’s findings are published in the journal “Monthly Notices of The Royal Astronomical Society”.
Ok, done, that’s it dear listener. Now let’s switch to chat about mushrooms and how to mix ‘em with French fries and vanilla ice-cream to create a very original wedding dress/combat suit for red ants of Papua New Guinea, ok? No? Are you sure? Still into this professor Rampino’s story? Oh well, you are the listener, so you decide.
So let’s start with some preliminary information before digging any further into Rampino’s paper, alright? Ok.
Our galaxy, the Milky Way, is a flattened spiral, so from a side view, well, it looks like a disk, or a funny pizza in case you look it when you’re particularly hungry, at least that’s what Silver Surfer said at the custom agents who interviewed him the first time he came by, and you got to believe a bald dude made of precious metal riding a space surf-table, right? I mean, who can be more reliable than a folk like that? Right?
Anyway, galaxy-flattened spiral-disk.
|Bernard and the Earth (by sciencemug)|
["NASA-Apollo8-Dec24-Earthrise" pic is a Public Domain image adapted by sciencemug (source: wikia.com)]
our Solar System travels around the galactic centre doing a full round every 250 million years (1). But the Solar System’s cosmic trip doesn’t follow a linear trajectory while circling around the galaxy’s centre. Nope.
The Solar System, and therefore our beloved planet Earth, goes up and down up and down like it’s riding a wave and therefore it periodically crosses, passing through it, the Milky Way’s mid-plane. This crossing happens once every 33-42 million years, astronomers say. Astronomers, besides, say also that our galaxy mid-plane is stuffed with a layer of dark matter, and that it takes about 1 million years to the Solar System to cross this slice of dark matter. Ah, by the way, let’s talk about this dark matter. Well, it’s a funny thing, the dark matter. It makes the 27% of the universe, it wildly influences gravity and yet it is invisible and it doesn’t interact with the matter we and the stars are made of (I’m not sure about Sheldon, though).
So, basically we don’t know anything final ‘bout dark matter. Of course some hyper smart dudes say that dark matter is the ultra-secret final solution of a conspiracy to make all humans, but a small group of gluten free ones, wear flip-flops also in winter and therefore become slaves obeying to the will of the members of the “New Galaxy Order” which involves the ObamaCare, NASA ESA JAXA and Roscosmos, the Reptilians (which are on tour, by the way, to promote their new album “I love Mikey Mouse*”, find it on iHumanoidTunes*) the lords of the “Hollow Earth” and all the people whose name starts with a letter that sound weird when pronounced at midday in a kitchen of a wooden house in a cloudy morning of an odd year. But for rest of us with an average intelligence (and for Elvis) well, we don’t know anything final ‘bout dark matter.
Ok, so, back to Rampino’s paper now.
The biologist from the Big Apple shows that, as for the crossing of the galaxy’s mid-plane, in the last half billion years of our planet’s life, mass extinctions and climate changes followed a circa 30 million years long cycle. Rampino shows also that, in the last 250 million years, peaks in the impact crater record, geomagnetic poles inversions and major geologic events followed a similar timing.
Rampino cites a study which shows that 77 of such geologic events followed the 30 million years cycle. The study analyzes tectonic episodes, changes in sea-ﬂoor spreading, sea level, oceanic anoxic events (that are sheer drops in the content of oxygen in the oceans’ waters) aaand continental ﬂood basalts (which are gargantuan eruptions of particularly fluid lava that end up covering huge areas of the emerged lands and creating layers of basalt).
Rampino goes on with his data mining and uses the collected numbers to draw a graphic where he plots mass extinctions, pulses in cratering records and continental ﬂood basalts of the last 260 million years against the cosmic trip of our Solar System up-through and down the galaxy’s mid-plane.
And, once the graphic is done, it shows something amazing, and hunting.
I’ll tell you about it after the commercial.
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|Terrorkill pill (by sciencemug)|
Try "Terrorkill", the new remedy based on curare and vitamin C.
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"Terrorkill", try it and you'll spend a peaceful night. Oor you'll die.
Sooo, back to Rampino and his plot now.
The plot shows that, and I quote from Rampino’s paper, “9 of the […] impact pulses correlate closely with times of mass extinction, 7 impact pulses correlate with ﬂood-basalt eruptions, 7 ﬂood basalts correlate with mass extinctions and 6 impact pulses can be correlated with estimated times of the Solar system crossing the
Galactic plane”. In other words, Rampino shows the existence of a correlation between Earth’s space trip through the Milky Way’s disk and catastrophes that our planet periodically suffers. Moreover, the professor statistically checks that such a correlation is unlikely due to simple chance.
So, at this point of the story even my dumb avatar’s tiny mind wonders a basic question: why. Why the passage of our system through the galaxy’s mid-plane has devastating effects on Earth?
Well, dear podcast-addicted, the answers, Rampino suggests, can be two: dark matter and gravity (I mean, gravity the force, not the movie… ahahaah, I made a joke… me funny blog). Anyway let’s start with gravity, more precisely with the galactic tidal force, which is not the title of a reboot of Battlestar Galactica with some drops of Baywatch in it. Nope, it’s really something related to gravity. Since our galaxy is a flattened spiral, most of its matter can be found in its plane and thus matter’s density drops off along an axis perpendicular to the plane.
|Earth vs comet (by sciencemug)|
Aaaand this tidal force can mess with the outer regions of our Solar System, those far away from the Sun’s strong gravity field that holds everything together pretty tight. In other words, the galactic gravitational tidal force can alter the orbits of the trillions of comets that form the Oort Cloud, the snow-balls reservoir that is from 75 hundreds million to 15 hundreds billion kilometers away from us. And if the orbit of those comets is messed up, well, those killer snow-balls can run toward the inner regions of the Solar System, that is toward our heads, and wipe out us all.
Sooo: crossing the galactic mid-plane, gravitational tidal forces, upset comets, impacts, mass extinctions.
But, what about the dark matter?
Well, well, Rampino says that the layer of dark matter within the galactic mid-plane is necessary to make the tidal force strong enough to annoy the Oort Cloud.
And Rampino says something else about dark matter bad influence on our planet’s fate. The professor says that, while Earth crosses the galactic mid-plane, dark matter particles scatter off protons and neutrons and therefore lose energy, get captured by Earth’s gravity and eventually accumulate in the Earth’s core. As the time goes by, the number of dark matter particles in our planet’s nucleus increases so much that their density gets high enough for them to start stumbling into one another and annihilate. And their mutual destruction is a process, Rampino says, that can release a massive amount of energy, enough energy to heat up the Earth’s core so much to affect the frequency of geomagnetic reversals and to cause devastating geologic phenomena like: pulses of tectonic unrest, changes in direction and rate of sea-ﬂoor spreading, volcanism, sea level and climate. In short to wipe out us all.
But, but, buuut, I feel you doubt that some invisible particles of some exotic matter can be tough enough to heat up the whole Earth’s core which has a mass of 2 thousands billion of billion of tons. Right? Well podcast-believer, truth is that you are wrong. And that’s why.
As I told you before, astronomers say that the galaxy’s mid-plane has a layer of dark matter within it. Earth can therefore encounter clumps of dark matter when it crosses the mid-plane, and these clumps can have a dark-matter density up to 1 billion times higher than average. Such a density is high enough for a huge amount of dark matter particles to annihilate and heat up our planet’s core of hundreds of Celsius degrees in just a bunch of thousand years. And given the fact that astronomers calculate in around 1 million years the time Earth will spend crossing the galactic mid-plane layer of dark matter, well, you see by yourself that there’s plenty of time for the dark matter to make Earth’s nucleus sweat, and therefore our asses be painfully kicked by all sorts of geologic nightmares.
Sooo, dear English-speaking-thinking-hearing visitor, to sum up, Rampino’s paper says that the Solar System and our planet go through the Milky Way’s mid-plane every 30-40 million years, and that mass extinctions, geologic catastrophes and peaks in crater records follow a similar timing. This coincidence, Rampino the Cassandra’s professor adds, can be due to the fact that crossing the galactic mid-plane can do two things that are bad for the health of us people of Earth:
1- alter the orbits of the comets in the Oort Cloud and make ‘em dive onto us
2- heat up Earth’s nucleus so much it sneezes geologic bombs that beat the deadly crap out of us.
Sooo, dear listener, if you wonder why Rampino spent all that time studying 30 years of data instead of going to some strip-club where kinky planets strip their rings off and show off all their curvy marvels, well, the answer is this: it’s always a wise thing to try to get more and more knowledge about what happened on Earth in the past, and why. Especially these days, when, you know, after roughly 30 million years since the last time, we're probably crossing a certain galactic mid-plane again.
Till next time then buddy! Well, eh, unless that mid-plane and the dark matter (or some lunatic) say otherwise…
William Will Whatever's note
I will pass over the absolute idiocy of this podcast since even a hint of critique of it would be just an unpardonable waste of my time. That this podcast made an utterly amateurish exposition of professor Rampino's interesting paper is indeed self evident. I just need to point out that, what this idiotic podcast generically (and superficially) calls "dark matter", in the original paper is more specifically (and precisely) described as dark matter composed by WIMPs (thus not by MACHOs, as someone so unlucky to listen to this podcast-garbage could be erroneously brought to think). You can find an excellent explanation of what WIMPs and MACHOs are in here and here.
If you tried and clicked those links, well, I really like your attitude, buddy!
ARTICOLO RACCONTATO NEL PODCAST/THE PAPER THIS PODCAST IS BASED ON
Rampino, M. R. (2015). Disc dark matter in the Galaxy and potential cycles of extraterrestrial impacts, mass extinctions and geological events. MNRAS 448, 1816-1820.
1- Nagai, D. (2014). Dark Matter May Play Role in Extinctions. Physics 7.