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What do you think killed the dinosaurs? A comet? A volcano? What about Dark matter?
Hey guys Julia here for DNews
Over 65.5 million years ago a comet slammed into earth sending a giant death plume of
debris into the atmosphere, killing almost all life on Earth including most of the dinosaurs.
We’ve figured this one out, we’ve got the evidence. A huge crater in the middle
of Mexico’s Yucatán Peninsula. But what sent that comet hurtling to Earth in the first
place?
Well some geophysicists like Michael Rampino, from New York University noticed something
strange in the fossil record. They found that every 30 million years or so, there seemed
to be a mass extinction. Some of these were smaller extinctions, but most of the big 5
mass extinctions match up with this timeline.
So what could be working like clockwork to trigger a great loss of life on this planet?
Well some scientists like Rampino have an idea. They point the finger at dark matter.
Yup that strange mass of something out there that we can’t see but only detect through
its gravitational effects on objects around it. Some estimates say as much as 85% of all
the stuff out there in the universe, is actually dark matter.
Theoretical physicist Lisa Randall suggests in her new book "Dark Matter and the Dinosaurs:
The Astounding Interconnectedness of the Universe" that dark matter might be responsible for
sending comets to Earth. So there might be dark matter concentrating near the center
of our galaxy, the Milky Way and forms a kind of thin cloud. Randall suggests that maybe
it’s more of a disk made up of particles 100 times larger than a photon. The disk might
be thin and dense. As our solar systems moves through the disk, it bobs up and down, like
an apple in barrel full of water. And those bobs are pretty regular, about every 30 million
years or so. Because the disk is so dense, the gravitational tug would affect planetary
bodies in our own solar system. It could even knock comets loose from their orbit in the
Oort cloud, a cloud of dust and comets, sending them towards Earth. And maybe this was the
case for the rouge body that slammed into Earth 65.5 million years ago.
But it’s not just rogue comets this dark matter cloud could trigger. It could trigger
volcanoes! That’s what Rampino suggested in an article published in the journal Monthly
Notices of the Royal Astronomical Society. He claims that the dark matter particles gather
in clumps in the disk. And those clumps get swept up by the Earth as it passes through
the disk. These particles collect in the center of the Earth where they reach sufficient densities
annihilate each other, producing enormous amounts of heat. This heats up the Earth’s
core by a few hundred degrees which expands the molten lava putting pressure on the crust
until it erupts in huge volcanic eruptions. Maybe huge enough to wipe out most of life
on the planet.
Though I should caution these ideas are still speculative at this point. There’s still
not a lot of evidence for a disc of dark matter in the center of our galaxy. There’s some
evidence that our nearest neighboring galaxy Andromeda might have one. And evidence of
our own is yet to come, the European Space Agency’s Gaia missions could reveal more
about dark matter. The mission will track the movement of hundreds of thousands of stars
throughout the Milky Way, through which we could learn about the distribution of dark
matter.
Till then, other scientists like Coryn Bailer-Jones, an astrophysicist at the Max Planck Institute
for Astronomy told Scientific American that they remain skeptical about such a hypothesis.
Some claim that the evidence is scarce for a clumpy dark matter disc, and others like
Bailer-Jones even question the periodic nature of mass extinctions. So while it’s a very
cool hypothesis, I mean who doesn’t love dark matter, dinosaurs and volcanoes in ONE
HYPOTHESIS? I’d say more research is needed.
You know what else is really cool together? CLONING AND DINOSAURS! Recently, we discovered
actual fossilized dinosaur eggs. Does this mean we're closer to cloning a dinosaur and
starting an awesomely terrifying theme park? Check out this video to learn more.
Hey Guys, if you like the shirt i have on and want to check out other DNews shirts be
sure to go to the link below. We have a ton of cool science shirts for your buying pleasure.
AND if you’re a first time buyer use the promo code DNEWS for 10% off at checkout.
    You must  Log in  to get the function.
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Did Dark Matter Kill The Dinosaurs?

743 Folder Collection
Serena published on November 9, 2015
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