by Mathew Brock, Mazama Director of Special Collections and Media;

Rose City Astronomers Volunteer Librarian.

The Perseid meteor shower stands as one of the most reliable and spectacular astronomical events of the year, painting the night sky with brilliant streaks of light each August. This cosmic display has captivated observers for over 2,000 years, making it a perfect introduction to meteor watching for newcomers and a beloved annual tradition for seasoned stargazers. While the peak of this year’s Perseid show will be overshadowed by a bright moon (just a few days after full), the brightest of the Perseid will still be visible and more than worth the show.

The Science Behind the Perseids

The Perseid meteors originate from Comet Swift-Tuttle, officially designated 109P/Swift-Tuttle. This massive comet, roughly 16 miles in diameter, orbits the Sun approximately every 133 years, leaving behind a trail of debris in its wake. Each year in mid-to-late August, Earth's orbit intersects with this debris stream, creating what we observe as the Perseid meteor shower.

When these tiny particles—think of a mix of grape nuts and grains of sand for scale—enter Earth's atmosphere at speeds of about 37 miles per second, friction with atmospheric molecules causes them to heat up and glow, creating the brilliant streaks of light we call meteors. The characteristic green color often seen in Perseids comes from excited oxygen atoms, while blues and purples indicate magnesium.

The shower appears to radiate from the constellation Perseus (hence the name), though meteors can appear anywhere in the sky. The radiant point sits between the constellations Perseus and Cassiopeia, rising in the northeast after 10 p.m. in early August and earlier each night as the month progresses.

Peak Viewing in the Pacific Northwest

The Perseid shower typically peaks around August 11–13, with rates of 50–100 meteors per hour under ideal conditions. The Pacific Northwest offers exceptional viewing opportunities due to its highelevation locations and often clear August skies. Here are some prime viewing spots: Mt. Rainier National Park offers spectacular dark skies, particularly at Paradise and Sunrise areas. The high elevation (around 5,400 feet at Paradise) reduces atmospheric interference, while the park's distance from major cities minimizes light pollution.

Crater Lake's rim drive represents one of the region's premier dark-sky locations. The caldera's elevation (6,000-8,000 feet) and minimal light pollution create ideal conditions.

North Cascades National Park features some of the darkest skies in the continental United States. Blue Lake and Sahale Arm provide excellent vantage points, though access requires hiking.

Mt. Hood area locations like Timberline Lodge and the ski areas offer good viewing, though slightly more light pollution from the Portland metro area may be visible. Snow Park parking lots also offer excellent locations for stargazing and meteor shower viewing.

Portland Metro area adjacent locations like Stub Stewart and Rooster Rock State Parks offer decent views under less than ideal conditions due to the significant light pollution from the city. For optimal viewing, arrive at your chosen location well before midnight. The best viewing should occur between midnight and 5 a.m, when Perseus is highest in the sky and the moon is lowest.

Planning Your Perseid Adventure

Be sure to check both the moon rise and weather forecast. As mentioned earlier, the full moon on August 9 will slightly diminish the best views. And as we all know, weather in the Pacific Northwest mountains can be

unpredictable; always check forecasts and prepare for temperature drops after sunset. Many mountain areas require permits or have seasonal restrictions, so research access requirements in advance. Popular locations may become crowded during peak nights, so consider exploring lesserknown high-elevation areas.

Remember that the Perseids continue for several weeks before and after the peak, offering multiple opportunities for viewing and photography. While peak nights produce the highest meteor rates, clear skies are more important than perfect timing—a clear night a few days off-peak often provides better viewing than an overcast or hazy peak night. For 2025, expect the first Perseids around midJuly (July 14–17), with activity gradually building through August until the peak on August 12–13, then quickly tapering off through late August and into early September.

The Perseid meteor shower represents one of nature's most accessible astronomical phenomena, requiring no special equipment beyond warm clothing

and patience. To locate the center, or radiant, of the Perseid meteor show, first locate the constellation of Perseus. To find it, use the Big Dipper by using the bottom left and top right stars in the pan and drawing a line through them continuing on roughly another four times the distance between the two stars, and this will take you straight to Perseus.

Whether you're watching with the naked eye from a mountain meadow or attempting to capture meteors through your camera lens, the Perseids offer a profound connection to the cosmos and a reminder of Earth's place in the vast universe.