Each group of teachers was assigned to think about the following:
An asteroid hits the Earth. What would be the ramifications of such
an event? How would this impact each of the spheres? You will realize
that there are some uncertainties that will depend on certain variables.
What are those variables concerning the impact that might modify
the effects of the impact?
Discussion:
Variables:
-
Location: Where did it hit? Land or sea? If it hit on land,
where? - Desert, mountains, areas of high or low population?
-
Size, as well as speed, angle:
If an impact is small then the season that it hits, might also be of importance.
-
Composition of the asteroid
Effects:
If the asteroid hits on land, there would be a huge amount
of dust thrown up into the atmosphere. If it hits in water,
then there would be an increase in water vapor in the atmosphere.
This would result in an increase in rain resulting in landslides
and mudslides.
Regionally there might be earthquakes, hurricanes and tsunamis
due to the increase in kinetic energy. If the asteroid is
large enough, these could be global in impact. |
image courtesey www.nasa.gov
|
Although speculative, the author, Michael Paine suggests the effects
of asteroid diameters of 1 km, 2 km, 5 km, and 10 km. He looks at
everything from the diameter of the crater to resulting firestorms,
dust storms and changes in the atmosphere and the effects on the
biosphere.
Resources on Mass Extinctions
Where
Did Everybody Go?
Teacher guide for a unit on the possible causes of mass extinctions
at the K-T boundary. Appropriate for grades 6-8.
Dinosaur
Extinction
A reasonably thorough and accurate, non-technical summary of the
hypotheses of dinosaur extinction, including (but not limited to)
asteroid impact. |