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The Webfooted Astronomer - February 2002

 

From the President’s Pen . . . Washington’s Best Places: Dark Clear Skies

By Mary Ingersoll

WHAT’S the Best Location in Washington State for Dark Clear Skies? This question is probably the most frequently asked on the club’s e-mail list server, Webftweb. As a service to those of you who do not have Internet access and for the benefit of those who may be tired of repeating themselves, I’ve compiled the answers members have given to that question. I would suggest you hold on to this copy of the newsletter for future reference.

Aside from one response (Arizona), many excellent recommendations and suggestions were given. My thanks to the people who contributed the following e-mail excerpts: Ken Applegate, Mary Anderson, John Angell, Sanders Chai, Greg Donohue, Ty Floyd, William Torgerson, and Dave Willingham. The responses below are not listed in any specific order, nor are they guaranteed. Updates and clarifications can be printed in a future issue.

I haven’t done this recently, but one of my favorite spots to just go and look at the sky used to be the old parade grounds at Fort Casey on Whidbey Island. The Milky Way used to be easily visible from there. I am currently the temporary “keeper of the WA State Observing Site” pamphlet [Sanders Chai]. It describes a few good sites. Here are a few updates:

Ironhorse at Snoqualmie is a big NO. Snowmobilers have taken over the place with RVs and portable generators.

Lookout Point on Bandera Mountain, exit 45 on I-90 is dicey at best with snow. I got up there partially with a 4WD, but had a #!@% of a time coming down because of ice. It looked very promising though, much better than Rattlesnake. I was able to see only the zenith because of trees (I wasn’t at the actual observing site; it was snow bound). It’s low enough in elevation that warming trends could easily make it passable. Take chains. [Check with Sanders in the late spring.]

Seriously, “clear dark skies” is a tall order for winter observing! Especially the clear part, when the whole state gets the same Pacific weather patterns to some extent. Eastern Washington will give you darker skies, although not completely dark, since Ellensburg, Wenatchee and Yakima put out their share of light pollution. One of the good locations, Table Mountain near Ellensburg, is basically snowbound and not accessible until very late spring. Also, getting to eastern Washington over snowy passes can be a problem.

For bright objects like the moon, planets, double stars, and star clusters, you can actually observe fairly well from our light polluted skies, if you can find a location not directly illuminated by the neighbor’s 600w Xenon security light. Parks looking out over Puget Sound are a good bet. Also, there are assorted filters that screw into standard eyepieces that help reduce sky glow and increase contrast for nebulae, for instance.

Sandy Shore Lake! Go west on highway 104 from the Hood Canal Bridge. About half way between the bridge and highway 101 there is a dirt road that goes south from Hwy 104. It leads to a lake called Sandy Shore Lake, and the road is Sandy Lake Rd. You only need to go about 1 mile on this road to a logged out area. Pretty good viewing there!

I recommend Rattlesnake Lake off I-90, exit 32. Just outside of North Bend. It is reasonably close and skies are not too bad. Directions are on Greg Donohue’s Web site (http://galaxyguy.bizland.com/viewing_sites.htm), or you can get them from him at the next club meeting (UW Astronomy building, 7:30 p.m., every third Wednesday. Check front page of newsletter for exact date.) And if the skies cloud over, you’re not to far from . . .

After three and a half years of frequent observing in eastern Washington, I would say eastern Washington is generally better for clear, dark skies than western Washington. However, from late fall until early spring, fog is a big problem in eastern Washington, which I have discovered to my surprise when I first started observing over there. I had no idea that eastern Washington is subject to more frequent foggy conditions than is western Washington. The fog can move in and obscure a clear sky in the time it takes to set up a telescope, effectively ending an observing session before it starts. On the positive side, I’ve also seen the fog lift as quickly as it moved in, usually about the time I’ve finished packing up my telescope in despair! To a certain degree the fog is unpredictable, but I usually look at the National Weather Service forecast for Ellensburg, Wenatchee, and the passes before I head over there. If it looks like a fog pattern is firmly entrenched or if the prediction is for “patchy fog,” I usually don’t go because I’ve found that the “patches” always seem to wind up where I will be observing. (The fog is more likely to occur at higher elevations, it seems.) As I write this, for example, current weather conditions in Ellensburg are “freezing fog,” even more delightful than the regular fog. Also, you might want to check the wind velocity forecast, because wind can be a big problem in spring in eastern Washington, although not so much of a problem in the other seasons. The URL for the Seattle weather map for Washington is www.wrh.noaa.gov/seattle/.

Because getting to eastern Washington can be a problem, you also might want to check the Washington Department of Transportation Pass Report on the Internet before heading over. The report gives forecasts and current conditions as well as live camera images of part of the passes and the chain-up area around Easton. As a rule of thumb, if the road is a white blur, bedecked with long lines of unmoving vehicles in the camera image, I don’t go because I’ve gotten into some tricky situations with the snowy road conditions that considerably dampened my observing enthusiasm for the moment. The URL for the pass report is http://traffic.wsdot.wa.gov/sno-info.

I have noticed that the best observing conditions occur in eastern Washington on the rare nights (4 nights in the past three and half years of consistent observing) when western Washington is also basking under clear skies. When there is a considerable difference in pressure and weather conditions between the two sides of the state, wind will often be a problem in eastern Washington, and atmospheric seeing conditions will be turbulent even though the skies may appear to be clear. Although you will find some very clear, good nights in western Washington during spring, summer and fall, my preference would always be for eastern Washington because the skies are always darker.

The south side of Poo Poo Point. Members have privileged access to the top of Tiger Mountain once a month. Though the road can be difficult (unpaved logging road; bring spare tire and tools), the viewing is good for a suburban Seattle site.

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