Starting January 12th 2014, Earth will begin going throughcomet ISON's dust trail from last November per NASA - 112,000 pounds per minute

Per NASA, the Earth will begin going through comet ISON's dust trail on January 12th, 2014, which will last for several days from when it was headed to the sun, last November. It will be coming from both directions, so the Earth will be getting it no matter which way it is directed. NASA has estimated comet ISON released 112,000 pounds of dust per minute at a rate of 125,000 miles per hour.