Velocity: 30 km per second (30 km/sec)
- How can we conceptualize this?
- 1000 times faster than the speed of a car on the interstate
- 150 times faster than a jet liner
- Six times faster than seismic waves
- Modeling this
- Time individual students in the class running ten meters
- Have students calculate velocities in meters per second
- Now convert meters to kilometers and recalculate speeds---How many times faster would the faster person in the
class have to run?
How Hard Did It Hit?
- 100 million megatons of TNT, or 100,000,000,000 tons of TNT
- What is this, using scientific notation?
- One hydrogen bomb = 1 megaton of TNT (At the peak of the Cold War, 10,000 of these existed, that we know of, anyway!)
- It hit us with such force that it created a crater 40 km deep, collapsed into a diameter of 150-200 km across
- That's definitely a big hole!
- Get those maps back out and draw that crater centered on your school
- Another activity for understanding cratering
- Containers of flour and various-sized marbles
- Students can experiment to see how trajectory and force affect cratering
What Happened When It Hit?
- Devastation at Ground Zero
- Bolide pushes through the thickest part of the atmosphere, creating a sonic boom
- Compression of air, heats it, creating a flash of light
- Shock wave travels down through limestone to granite bedrock, destroying crystal structure
- Second wave or backward reflection of ground pulverizes the trailing edge of bolide
- A Few Hundred Miles Surrounding the Impact
- Ejecta of debris flies into outer edge of the atmosphere
- Cloud of vaporized rock is driven outward in a fireball
- A second fireball occurs as limestone suddenly releases its CO2
- A Few Thousand KM Away
- Seismic waves would shake the earth
- Earth/ground would grow hotter as ejecta falls back to earth
- Air blackened by smoke fires, using up available O2
- Marine landslides produce earthquakes, resulting in tsunamis
Further Out---Global Implications
- The fires from the impact would have been gone within days
- Dust would still not settle out of the atmosphere for a few months
- Darkness and cold as solar energy were reflected into space
- CO2 and H20 were thrown into space
- Water would fall as rain until the atmosphere was no longer saturated
- Carbon Dioxide remains in the atmosphere for a long time, trapping heat once the sun's rays return
- Acid rain would prevail
- Carbonic acid, of course, rain falling through it
- Sulfuric acid, impact into gypsum would put large amounts of sulfur into the atmosphere
- Nitric acid---the air would be strongly heated from the impact
- Lots of nitrogen in the atmosphere but with heat added: N2 + O2 --->2 NO
NO contacting rain would form HNO3---a bad day to be caught in the rain!
T. rex and the Crater of Doom
Walter Alvarez
0-375-70210-5
Copyright 1997
The Way Science Works
- Lessons from Alvarez
- Science involves...
- Collaboration
- Serendipity
- Fighting the prevailing theory
- Integration of disciplines
- Communication
- Data collection
- Replicable results
- Human endeavor
- Ethical behavior
Dr. Robert Behling (rbehling@wvu.edu)
Dr. Jack Renton (jrenton@wvu.edu)
Dr. Deb Hemler (dhemler@mail.fscwv.edu)
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