That asteroid entered the atmosphere and exploded, leveling trees over an area of 820 square miles -- about two-thirds the size of Rhode Island.

CNN: Russian meteor shower causes blast; hundreds injured

For sky watchers, the reports bring to mind the famous Tunguska event of 1908 in remote Siberia, in which an asteroid entered the atmosphere and exploded, leveling trees over an area of 820 square miles -- about two-thirds the size of Rhode Island.

CNN: SHARE THIS

In that incident, an asteroid entered the atmosphere and exploded, leveling about 80 million trees over an area of 820 square miles -- about two-thirds the size of Rhode Island -- but leaving no crater.

CNN: Russia starts clean-up after meteor strike

In an area previously the exclusive domain of only the biggest brands with the biggest budgets, this is a real leveling of the advertising playing field.

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