The Orionids—one of two major meteor showers caused by remnants from Halley's Comet—will peak this week, though a large moon will dim visibility until after it sets late at night. During the peak Wednesday night into Thursday morning, it will be possible to see up to 20 meteors per hour under ideal viewing conditions, according to the American Meteor Society. Meteors are still visible for a few weeks before and after the peak. The Orionids are viewable in both the northern and southern hemispheres after midnight. While they get their name from the Orion constellation, they are visible across the night sky, according to NASA. Orionids can be especially bright and fast, and can leave glowing trains that can last for several seconds. Here's what to know about the Orionids and other meteor showers, per the AP: