(CNN) -- From San Francisco to Monterey, California, people may not have been aware that the Orionid meteor shower started Tuesday, but they got a startling wake-up call as many people spotted a fireball streaking overhead.
About 7:45 p.m. Wednesday, what a scientist at the Chabot Space & Science Center in Oakland described to a local ABC news station as a "small car-sized piece of rock and metal" lit up the night sky and rattled windows with sonic booms.
While most reports came from around the San Francisco Bay area, there were sightings reported as far south as the Pebble Beach area, with one person managing to get a snapshot of it from the Salinas Valley region, farther inland.
At the moment, it is not entirely clear whether these were different meteors or the same one seen from different angles.
This may have been an unexpected bit of excitement for Californians, but it's a safe bet that a lot more people all across the Northern Hemisphere will be looking up between now and when the Orionid meteor shower reaches its peak on Saturday night, in hopes of seeing another spectacular light show.
Several meteor showers occur regularly throughout the year, thanks to the Earth's passage through the debris fields left in the wake of comets or asteroids on their regular orbits around the sun.
The Orionids, so named because the angle at which the Earth intersects their path makes it appear as if they originate in the constellation of Orion, are one of the brightest and most densely packed meteor showers.
They're the leftovers of Halley's Comet on its regular trip through the solar system. Being spawned from a comet imparts the Orionids with the relatively high velocity of 148,000 mph as they strike the Earth's atmosphere, which make for an especially bright show.
Although Halley's Comet won't be back around until the year 2061, the debris that has broken off the comet stays along the same orbital trajectory and burns up in the Earth's atmosphere every year.
The debris that makes up the Orionid meteor shower crosses our path for about a week every October, while the other leftovers from Halley's Comet come in the form of the Eta Aquarid meteor shower in May.
The Orionids will peak in the dawn hours of Sunday. Want to watch? Get as far from city lights as you can, and look east/southeast. We'll have more on the Orionid shower Friday, complete with an iReport assignment!