Google Earth and Google Maps keep on turning up useful items for the amateur astronomer. The first image on the left (click to enlarge) is from the impact craters section
. This image shows the Acraman crater in South Australia, one of the top 10 impact craters world wide. Around 590 million years ago, a bolide impact blaster out this 90 km diameter crater and scattered ejected for 560 km around the impact point. Ejecta from this event got as far as Adelaide, and I have traced the ejecta line in the Flinders ranges. The only organisms around at the time were small squish wormlike things, but the impact would have been devastating to them. The geology.com site allows you to explore the 50 most obvious impact craters in the world.
In contrast, the Meteor Impact database
for Google Earth
has data from around 26,000 meteor impacts in 127 countries, with a wide range of data on the meteors themselves. The image to the left shows meteors recovered near Adelaide (click to enlarge), but the database is breathtaking in its coverage. You can download the KML file directly here