Skywatchers will have ideal viewing conditions to watch the annual Perseid meteor shower, which will peak this weekend, between August 10 and 13.
Named for the Perseus constellation from which it originates, this meteor shower is visible every year in August when Earth passes through debris from the comet Swift-Tuttle. A short-period comet, Swift-Tuttle takes 133 years to circle the Sun. Each time it makes its closest approach, the Sun’s heat and tidal forces cause pieces of it to break off, leaving behind a debris field.
The Perseids will be especially bright this year because the meteor shower occurs at the new Moon, when the Moon will not be present to brighten the sky and obscure the meteors. Night skies without a Moon are darker and provide the best opportunities for meteor viewing.
“This year, the Moon will be near new Moon; it will be a crescent, which means it will set before the Perseid show gets underway after midnight. The Moon is very favorable for the Perseids this year, and that’ll make the Perseids probably the best shower of 2018 for people who want to go out and view it,” NASA meteor specialist Bill Cooke told the website Space.com.
On Saturday night August 11, viewers with dark skies should be able to see between 60 and 70 meteors per hour. An online map of areas across the country with the least light pollution, created by a research team at the Cooperative Institute for Research in Environmental Sciences (CIRES) and Chris Elvidge of the National Oceanic and Atmospheric Administration (NOAA) is available to guide viewers to the best locations.
Both the brightness of meteor showers and the number of meteors visible are determined by several factors, including the density of the debris field, the debris field’s relative speed in relation to Earth, the distance between Earth and the debris field, and the degree of light pollution at a viewing site.
Observers should allow approximately 30 minutes for their eyes to adapt to the dark.
While the shower peaks this weekend, Perseid meteors can be seen any clear night between July 17 and August 24.