Stalking planetary nebulae from Seattle

Despite a recent run of decent weather in Seattle, the night skies have often as not been cloudy, thus limiting opportunities for astronomical observations. Thus when the stars aligned last night with crystal clear skies, an evening without work, and a reasonably alert stargazer, I dragged the telescope out into the back yard for the first time in a while to hunt for some planetary nebulae.

The Hubble Space Telescope is a slightly more powerful instrument
than your correspondent's 8-inch Dob located in a light-polluted
 urban back yard. The Saturn Nebula didn't look quite like this
from West Seattle; there was a hint of the color but none
of the detail of the object in this Hubble image.
Photo: STSci, NASA.

The targets, NGC 6818, the Little Gem, and NGC 7009, the Saturn Nebula, were chosen because they’re in prime viewing spots in the southern sky these days, and because they’re among the remaining few objects left to be checked off as I work toward the Astronomical League‘s Urban Observing Club recognition. The clubs are a good way to organize one’s observing. The Urban Club list includes 100 objects, all reputedly visible from light-polluted skies, defined by the club as places where the Milky Way is not visible with the unaided eye. I say “reputedly” because several of the galaxies on the list have been extremely difficult to see from my back yard. But, if it was too easy, what would be the point? View all 100 and you get a nifty pin, and your name is added forever to the club membership rolls.

Last night’s nebulae were both easy to locate but tougher to see. NGC 7009 was easier, spotted very near the star Nu Aquarii in the constellation Aquarius. It appeared in the eyepiece of my 8-inch Dobsonian as a greenish-blue blob, with details such as the “rings” that earned it its nickname visible. Higher power definitely revealed more nebulosity, but washed out the color completely. The Little Gem was a bit tougher, just to the west of a “peace sign” asterism in Sagittarius. A couple of magnitudes dimmer than the Saturn Nebula, NCG 6818 revealed just the slightest hint of color. The moon was not helpful with these objects, as it was just a few days past full and low in the east during the pre-midnight hours during which I was observing.

I visited a few old friends during the evening, including the double cluster and the Ring Nebula, before calling it a night a little before 1 a.m.