Sky watchers will be treated to a rare double occurrence of the Leonid meteor showers this month, although the celestial light show is expected to be a pale encore to last November's stunning display.
The first opportunity is tonight. Starting at around midnight, viewers in Los Angeles who can get to areas free of urban light could see up to 12 meteors an hour, according to various predictions collected by Bill Cooke of NASA's Marshall Space Flight Center in Huntsville, Ala.
But astronomers warn that predicting the intensity and exact time of meteor showers remains an inexact science. Complicating matters, a bright gibbous moon may outshine many of the meteors.
A similar show is expected Nov. 19 and could provide better viewing because the waning moon will not interfere as much. Viewers should look toward the eastern horizon between midnight and 2 a.m., said Scott Kardel, public affairs director of Palomar Observatory in San Diego County.
"It's pretty unlikely we're going to have a huge outburst," he said.
The Leonid meteor shower occurs each November when the Earth passes through dust trails shed by the comet Temple-Tuttle, which soars through the inner solar system every 33 years.
For the last four years, Earth has passed directly through fresh dust trails and allowed some viewers to see more than a thousand meteors per hour. This year, the planet only brushes past dust trails that are several centuries old.