Meteor showers occur when our planet orbits through the dust streams created by a number of well known comets. For example, Halley's Comet is the source of the Eta Aquariids and Orionids, in May and October, respectively.
If the May 24 "surprise" meteor shower shows up, it will be called the "May Camelopardalids," but forecasters are at odds as to how many meteors it will generate, if any.
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The problem, experts argue, is that although we know Earth will pass though Comet 209P/LINEAR's path, it is a path that was laid down in the 19th Century, over 100 years before the comet was discovered. We simply do not know if the comet was active back then - there is no observational data or reports of sightings. If it wasn't active, very little dust will have been released into space, making the Camelopardalids a non-event.
"We have no idea what the comet was doing in the 1800s," said Bill Cooke, head of NASA's Meteoroid Environment Office. "There could be a great meteor shower - or a complete dud."