For Evanstonians, the annual Perseid meteor shower will peak between tonight and tomorrow and the same times the following night. According to the website of the Adler Planetarium, “When Earth passes through the orbit of a comet, the leftover debris bombards Earth and burns up in our atmosphere, creating a meteor shower. Some meteor showers occur regularly, including the Perseid meteor shower that occurs every August when the Earth passes through the orbit of comet Swift-Tuttle. … If you could trace back the paths of the meteors you see, you would notice the paths trace back to a region in the direction of the constellation Perseus. This is why the shower is called the ‘Perseid meteor shower.’ The meteors aren’t really originating from this constellation, but instead are from left-over debris from the Swift-Tuttle comet.”

The website says astronomers expect “up to 200 meteors per hour in short bursts of up to 15 minutes or so. But many of the fainter meteors will simply not be visible due to moonlight, and rates will go down even more for those in urban areas. More likely a typical observer under reasonably dark skies might hope to see a meteor every couple minutes when the bursts come, and fewer during lulls.”