Update: looks like the selling has stopped for now. NASDAQ OPTIONS MKT REOPENED FOR TRADING, SPOKESMAN SAYS
If one has no access to a market pricing service, perhaps the simplest and easiest way of testing if the market is down, is to check the NASDAQ market system status [3]page. Usually, on down days, the NASDAQ just, well, breaks. As it did moments ago when it announced that trading in options with a symbol range A through M has been halted.
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