Remember the Stop Disasters game from last week? Now you can use an impact model program to wreak some havoc on Earth!
Go to https://www.purdue.edu/impactearth. Impact: Earth! is an easy-to-use, interactive website for estimating the regional environmental consequences of an asteroid or meteor impact on Earth. The program was developed by faculty and graduate students at Purdue University, Imperial College London, and the University of Arizona. Simply enter values in the boxes to describe your impact event of choice and your distance away. The program will then estimate the atmospheric blast wave, ground shaking, ejecta distribution, and thermal effects of the impact as well as the size of the crater produced. Take some time and play around with the site. (Have patience if it runs slow, it’s doing lots of calculations.)
You will want to run multiple simulations to compare the differences between impact types. The best way to do this is to run a controlled experiment to see how one single factor can affect the outcome of an impact. Change either the diameter, the density, or the target (one at a time) but set all of the other parameters the same each time and DON’T change them. My son triggered a tsunami with a schoolbus-sized impactor, but when he changed it to a moon-sized impactor (with everything else staying the same), the Earth was completely blown away and its debris forms a new asteroid belt orbiting the sun between Venus and Mars. (Note that these are estimates based on current limited understanding of the impact process and the scenarios come with large uncertainties.)
The Impact: Earth! site includes a glossary of terms along with a list of famous craters and their statistics, as well as a PDF document that details the observations, assumptions, and equations upon which this program is based. You can also try out a version of the program that is still under development to map the effects of an impact in a specific city or place somewhere on Earth. (This one requires a Google Earth plug-in and is still being tested.)