This week sees the start of the year's most famous meteor shower, the Perseids. Peaking each August, the Perseid meteor shower is the most popular and celebrated in the Northern Hemisphere thanks to its coinciding with warm summer nights, but this year, an awkwardly-timed full moon means some careful planning is required to avoid a washout.
A Perseid meteor streaks across the sky during the Perseid meteor shower in Vinton, California, Aug. ... More
The Perseid meteor shower is active from July 17 through Aug. 23, peaking overnight on Aug 12-13.
The peak night provides around 50-75 meteors per hour, but in 2025 that will be reduced by about 75%, according to the American Meteor Society.
The problem in 2025 is a full sturgeon moon, which rises on Aug. 9 and will still be very bright on Aug 12-13, rising just as the peak of the Perseids gets underway and remaining in the sky for the rest of the night.
The darkest skies closest to the peak are from July 18-28 and Aug. 16-26, all far from the peak nights, with only very reduced rates possible.
July 29-30 sees the peak of two other meteor showers — the Southern delta Aquariids, which offers 25 shooting stars per hour, and the alpha Capricornids, with about five, though they tend to be bright "fireballs."
Another option is to wait until Aug. 15, when the moon will rise around midnight close to the Pleiades open star cluster.
If you're planning to observe meteors, make sure the moon will be down. After all, it's the biggest light polluter there is in the night sky and will render pointless a trip to dark regions on a light pollution map or a Dark Sky Place. As well as a dark sky, a clear sky is required, so check the weather forecast in advance. Find somewhere with a clear view of as much of the night sky as possible, packing extra layers to keep warm, as well as bug spray, snacks and drinks. Be patient, giving your eyes at least 30 minutes to dark-adapt before expecting to see shooting stars. Take a break every 30 minutes and avoid looking at a smartphone, which will kill your night vision.
All meeor showers are caused by streams of dust and debris left in the inner solar system by comets or large asteroids. In the case of the Perseids, it's Comet Swift-Tuttle, which at 16 miles (26 km) has the largest nucleus of any comet known to regularly pass close to Earth. That's about twice the size of the asteroid believed to have wiped out the dinosaurs, according to Space.com. It was last in the inner solar system in 1992 and will next visit in 2125.