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Ep350: Inside the Chicxulub Asteroid Impact · Kidcast Daily

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  Spin the wheel, let's take a ride.
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  Sports and science bursting from inside a world of wonder open
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  wide. Come on kids, let's amplify kid
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  cats. Daily starts your day.
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  Fun and laughter come your way. Sports and trivia games galore.
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  Hey there, Pitcast Daily is back and today we're diving deep
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  covering everything from record-breaking athletes to
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  incredible science, amazing animals and beyond.
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  First up, let's travel back in time all the way to about
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  66,000,000 years ago to learn what scientists have discovered
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  inside the Chiksilab asteroid impact.
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  This was a giant space rock that hit what is now the Yucatan
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  Peninsula in Mexico. The impact changed our planet's
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  environment and left a huge circular scar under the ground.
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  Today, we're going to explore what is inside that crater, how
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  scientists found it, and what clues it holds about Earth's
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  past. Here is a trivia question to
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  kick things off. Which small town's name is used
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  for the crater where the asteroid hit?
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  The answer is Chicksila Pueblo, a town near the center of the
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  Yucatan Peninsula in Mexico. The crater is named after this
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  town because it sits near the center of the buried structure.
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  Now, what made this impact so extraordinary?
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  Scientists estimate the asteroid was about as wide as a large
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  city, around 11:50 kilometers across.
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  It hit Earth very fast, likely faster than a jet by many times,
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  and released a huge amount of energy.
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  The ground near the impact site broke, melted and moved like
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  waves in a pond, but on a scale that involved rock.
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  This created a special kind of crater with a raised inner ring
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  called a peak ring. Chicxulub is one of the best
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  examples of a peak ring crater on our planet.
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  You might be wondering how anyone knows this when the
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  crater is mostly hidden beneath rock and sediment.
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  Here is a yes or no question. Is the Chicksilub crater mostly
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  underground and partly beneath the sea today?
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  Yes. Most of it is buried under the
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  Yucatan Peninsula and extends into the Gulf of Mexico.
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  Scientists used gravity measurements, magnetic surveys
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  and drilling to map it. Gravity maps showed a big
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  circular area with lower density rock outlining the craters rim
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  and inner structures. A key feature inside the crater
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  is the peak ring. Think of a circular Ridge inside
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  the crater, not on the outer edge but closer to the middle.
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  During the impact, rock from deep underground was pushed up
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  quickly, then settled into this ring.
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  What kind of rock is found there?
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  Geologists discovered granite and similar deep crustal rocks
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  that were moved upward in seconds.
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  That is one of the reasons Chicksilab is so famous in
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  geology. Time for another yes or no
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  question. Did the Chicksilab impact
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  generate large ocean waves that spread across nearby seas and
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  even between continents? Yes, The impact sent out
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  powerful waves around parts of the Gulf of Mexico and beyond.
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  Layers of disturbed sand and mixed sea life show signs of
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  strong, sudden water movement. These layers match the timing of
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  the impact. Now let's look even closer at
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  the rocks themselves. Inside and around the crater are
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  materials that formed during and after the strike.
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  There is melted rock that cooled into glassy or crystalline
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  forms. There is breccia, which is a
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  jumble of broken rock pieces stuck together.
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  There are also tiny round droplets called spherols, which
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  formed when molten rocks sprayed into the air, cooled while
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  falling, and piled up in layers. These spherols have been found
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  far from Mexico, showing how far the impact materials spread.
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  Here comes a trivia question about a special clue in the
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  rocks. What kind of common mineral
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  shows microscopic lines and patterns that only form during
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  extremely high pressure from an impact?
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  It is quartz, and the special form is called shocked quartz.
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  The lines inside the crystals are like a record of the sudden
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  pressure wave that moved through the rock.
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  Finding shocked quartz help scientists confirm an impact.
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  Right after the impact, dust and tiny particles filled the air.
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  Rocks that contained sulfur released gases.
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  When heated, these particles and gases rose high in the
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  atmosphere and blocked sunlight for a while.
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  That made air temperatures drop and changed how plants and
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  animals could live in many places.
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  Over time this cleared and sunshine returned, but the short
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  term cooling and darkness made life very challenging.
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  Scientists can trace this event in sediments all over the world.
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  Let's add a new fact with a trivia question.
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  Which element, rare in Earth's crust but common in some
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  asteroids, forms a thin layer in rocks worldwide at the time of
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  the impact? The answer is Iridium.
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  A thin Iridium rich layer is found in many places, from Italy
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  to New Zealand. This worldwide marker shows the
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  timing of the event and links it to space rock material.
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  One of the most exciting parts of studying the crater happened
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  recently. In 2016, an international team
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  drilled into the peak ring using a special platform that can stay
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  steady at sea. Cores of rock were brought up
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  like long cylinders, each one telling a story.
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  The course showed broken, melted and shocked rocks, plus pieces
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  of deep crust lifted up during the impact.
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  The structure of the cores help scientists model exactly how the
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  ground moved in those first minutes.
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  Here is a trivia question that adds a fresh detail.
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  What year did scientists begin retrieving long rock cores from
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  the Chicxulub Peak Ring during a major offshore drilling project?
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  The answer is 2016. That project gave researchers a
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  direct look at the rocks that built the peak ring.
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  Inside those cores, scientists also found evidence of how
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  quickly life returned. In the layers above the chaotic
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  impact rocks, tiny marine fossils appear.
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  These fossils show that microorganisms began to grow in
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  the water not too long after the event.
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  As sediments continued to collect, larger and more complex
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  life forms show up again in the record.
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  This tells us that even after big changes, ecosystems can
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  recover over time. Let's try another yes or no
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  question that introduces a new angle.
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  Have scientists found microscopic glassy beads from
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  the impact stuck inside tree resin that later turned into
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  amber? Yes.
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  In some places tiny spherols have been found preserved in
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  amber. This shows that material from
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  the impact fell into forests far from the crater and got trapped
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  in sticky resin drops. Another inside the crater detail
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  is the arrangement of faults and fractures.
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  The impact created rings of broken rock zones.
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  Water moved through these spaces carrying minerals that later
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  filled cracks with new material. Some of these minerals help date
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  the events after the impact. By measuring radioactive
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  elements in minerals, geologists can calculate when they formed,
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  like reading a very slow clock inside the rock.
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  Did you know that the Chicxulub crater is roughly 200 kilometers
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  across? That span is wide enough to
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  stretch across multiple large cities in a row.
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  The depth right after the impact was greater than it is now
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  because rocks relaxed and settled over time.
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  The peak ring stands as evidence of the dramatic uplift that
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  happened in just minutes. Scientists use computer models
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  to test how an asteroid traveling at different speeds
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  and angles would make a crater like Chicxulub.
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  By matching models with the rock evidence, they estimate the
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  asteroid came in from a shallow angle, which helps spread debris
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  widely. This kind of research improves
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  safety planning today because it tells us how impacts work and
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  what signals to look for in rocks and in the atmosphere.
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  Let's wrap up with a quick recap.
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  The Chicksalub crater lies mostly buried under the Yucatan
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  Peninsula and the Gulf of Mexico.
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  It formed 66,000,000 years ago when a large asteroid struck
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  Earth. Inside the crater is a peak ring
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  made of uplifted deep crustal rocks, including granite and
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  rocks that were melted and broken.
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  Evidence like shocked quartz spherols and a global Iridium
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  rich layer tells us about the force of the impact and how its
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  effects reached around the world.
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  Drilling in 2016 brought up course samples that confirmed
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  how the peak ring formed and showed how life gradually
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  returned in the ocean above the crater.
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  By studying these details, scientists learn how our planet
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  responds to sudden changes and how clues inside rocks can
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  preserve a clear record of events long after they happen.
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  And. Beyond breakfast, feeling fine.