MANILA, Philippines?Look up at the night sky on Nov. 17 and you may view a spectacular meteor shower, possibly even a meteor storm, meteorologists said.

Radiating from the constellation Leo, the Leonids meteor shower occurs annually at this time of the year when the Earth passes through streams of debris left behind by the Tempel-Tuttle comet centuries ago.

The Philippine Atmospheric, Geophysical and Astronomical Services Administration (PAGASA) said the Leonids is ?one of the most prolific? meteor showers with its peak at about 11 p.m. on Nov. 17 to 6 a.m. on Nov. 18.

The Leonids generally begin on Nov. 13 and end on Nov. 21.

?If the skies are clear, we will have a maximum of 100 meteors per hour,? said Renato de Leon of Pagasa?s Observatory. ?The Leonids is considered one of the most spectacular meteor showers. It would be exciting to watch and we are hoping for clear skies.?
The US National Aeronautical Space Agency (NASA), on the other hand, predicted the showers could reach 500 meteors per hour, making the 2009 Leonid showers a ?half-storm.?

A meteor storm is defined as 1,000 or more meteors per hour.

?On Nov. 17, 2009, we expect the Leonids to produce upwards of 500 meteors per hour,? said Bill Cooke of NASA last year. ?That?s a very strong display.?