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Perseid Meteor Shower Information
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The Perseid Meteor Shower occurs each August as the Earth, following its normal orbit around the Sun, intersects the orbit of dust particles left behind by comet Swift-Tuttle. Think of this event as a car on a road driving through a chute of snowflakes. In the case of the meteor shower, these dust particles -- all of them tiny specks -- become extremely hot as they hit the Earth's upper atmosphere at speesd of 20-50 miles per second. The hot particle generates a streak of light before the particle is obliterated.

The best time of the night to observe the event is when your viewing point is facing into the dust stream, much as the best way to snowflakes while driving is to look forward (through yor windshield). This occurs when the pre-dawn side of the Earth is moving towards the constellation Perseus-- i.e., early in the morning. (Thus the name of the meteor shower.). That's when the count rate of events reaches its peak. However, the occasional stray dust particle can be seen burning up in the evening as well, particularly once the sky is dark.

There are several meteor showers during the year, the best of which is the Leonids in November. For people on the west coast of the U.S., the advantage of viewing the Persieds is that they occur during the summer season of clear, relatively warm weather. The moon will be in almost new, so the sky will be brighten only slightly after about 2 AM.

Check with theOregon Museum of Science & Industry (OMSI) for news of their annual public "Meteor Party".

To learn more, go to the web page of the American Meteor Society

Click any of the images for an enlargement

Left: Where to look for the highest concentration of events.     Right: The view from above: the Perseids from an orbiting satellite.

Before you go, here are some tips for making the trip enjoyable.
  • It may be cool at night, especially when sitting out for hours, so bring warm clothes and drinks.
  • You'll be staring up and to the east for quite a while, so bring a blanket, and a comfortable pad or chair.
  • Count rates are typically 40 events per hour, more in some years than others, and more at dark sites than bright ones.
  • The Persides extend throughout August; however, the best nights are usually August 11, 12, and 13. The expected peak of the shower is before dawn on August 12-13.
  • The best viewing hours are between 2 and 4 AM when the Earth's face is facing into the grain/pebble swarm.
  • Cameras and bioculars won't do much good for seeing meteor showers. Yes, really. Bring them for other purposes, such as viewing the moons of Jupiter.
  • Faint streaks are far, far more common then bright ones. That's because the particles hitting the atmosphere are mostly grains with a few tiny pebbles.
Wondering where to catch a glimpse of this event? Below are thoughts from various UW astronomers on their favorite viewing spot:

1. "Camano island is nice. There's a good state park campground there."

2. "Below Rattlesnake Ridge right near North Bend is only 45 minutes away and gets you on the other side of the first foothills so that most of the Seattle light is blocked out and you get nice dark skies."

3. "I have seen them from up near Snoqualmie Pass. I just took some logging road and found a clear spot. It was great."

4. "To reverse a famous phrase: "go East, young lady, go East!" After crossing Snoqualmie Pass go on to the road to Roslyn. Stop wherever there is open viewing to the NE and no nearby lights."

5. "We went to the old Snoqualmie winery spot a few yrs ago for the Perseids and it was full of people with the same idea - its a perfect spot. It's one of the exits before the pass."

6. "Contact the Seattle Astronomical Society. They do local star parties on Tiger Mountain though I don't know if camping is possible there. I've also stayed nearly all night just in a field off the side of the road that goes north from Fall City (just north of I90)...seems ok for those few hours, but not for camping. Don't go any closer to the Cascades though, the north-eastern sky will be blacked out by mountains. Personally? I'd go past the Cascades to Easton or Cle Elum. I'd look at a map of State camp grounds, then estimate where the mountains are and the campground can tell you about the tree cover."

7. "I prefer old route U.S. 10 (now WA 10) near I-5 a little east of Cle Elum. The site is easy to reach from Seattle, extremely dark, scenic, with good parking at various turnouts along the river. Winds are generally quiet."

8. "Easiest one: Out near Carnation (head I-90 east and hook north on Preston-Fall City road (exit near North Bend). 30-45 minutes away."

9. "Better ones: Just go to any isolated camping location. The coast works well, but is often cloudy. Probably the best bet would to head over the mountains and catch it near Vantage (just East of the mountains as I-90 crosses the river.) Heck, just about anyplace in eastern washington works other than the 3 population centers."

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