Lake Sonoma 8/30/08

Steve Gottlieb

We had a nice turnout last night (Saturday) at Lake Sonoma with good transparency for hunting down faint fuzzies, though a pesky breeze kept conditions a bit uncomfortable at times and seeing was a bit soft. At the Rock Springs lot were Matthew Marcus (back from China), Dana Patchick (discoverer of several objects including supernova 1987L and a few planetaries/emission objects), Dave Staples (and daughter), Michael Porteusi and Jim Mace. Seeing started off fairly rough, but improved enough that I could use 280x with good images. I had to drive back to Albany by 2:00AM due to family commitments on Sunday, but Matt and Dana continued observing.

Here's a rundown of the highlights with my 18" Starmaster --

Barnard's Galaxy -- the galaxy was easy enough to see in my 18" (I've viewed it fairly easily in my 80mm finder at 25x and even in hand-held 15x50 IS binoculars), but I focussed on the "bright" extragalactic HII regions on the north end of the galaxy. These are sometimes referred to as Hubble V and Hubble X (IC 1308). Both were discovered visually in 1887 using a 26" refractor and they're visible as small knots that respond to narrowband filters. Hubble V was picked up unfiltered at 175x as a small, 20"-25" glow, just 1' NW of a mag 12.5. Hubble X = IC 1308 is located 3' due east and has a slightly lower surface brightness, spanning 25"-30".

Sharpless 1-89 = PK 89-0.1 (21 14 07.6 +47 46 22) -- this faint planetary was easily picked up using the OIII filter at 115x though I missed it unfiltered at 175x or 115x. Adding a filter, Sh 1-89 appeared faint, fairly small, elongated NW-SE, ~40"x30", with a reasonably crisp outline. Without a filter a faint star is at the SE end of the planetary. On the DSS image, very low surface brightness bi-polar wings extend out from the main body, though I couldn't pick these up. Located in a rich star field 20' E of the open cluster IC 1369.

Minkowski 2-53 = PK 104-1.1 (22 32 17.7 +56 10 26) -- I missed this planetary unfiltered at 115x, but it was easily picked up using an OIII filter as a faint, small, circular disc, ~15" diameter. Upping the magnification to 280x, the planetary was visible continuously using averted vision. The contrast increased further adding a NPB filter and there was no problem holding it continuously as 12"-15" crisp disc. Located 2.6' SW of a mag 9.6 star and 2.5' N of a 20" pair of mag 12.5 stars.

Abell 61 = PK 77+14.1 (19 19 10.1 +46 14 36) -- picked up fairly easily at 73x using an OIII filter as a large, low surface brightness, roundish glow, ~3' diameter, in a rich Milky Way field. This large planetary could be held continuously using averted vision once I identified it in the field and the rim was slightly better defined on the west side. An elongated group of stars is close SW including several in a NW-SE string.

Abell 70 = PK 38-25.1 (20 31 33.2 -07 05 17) -- easily picked up unfiltered at 283x using the 8mm Ethos as a small, round disc, perhaps 30"-35" diameter. What makes this object special is an edge- on galaxy that shines through the north side of the rim! There's an excellent image of the planetary/galaxy pair at http://www.noao.edu/ outreach/aop/observers/abell70.html. The galaxy on the north edge of the rim was mostly visible as a very small knot and only occasionally appeared elongated 2:1 ~E-W.

IC 5148 = PK 2-52.1 (21 59 35.1 -39 23 08) -- this is one of my favorite planetaries in the sky though at -39 degrees dec, it's buried deep in the southern sky from northern California. I had a beautiful view at 115x using an OIII filter as a 2' annular ring with a relatively thick rim and 30" central hole. A mag 10.5 star is close off the SSW side (1.8' from the center). This was a stunner from Australia where it passes a few degrees from the zenith.

Kronberger 54 (20 03 07.9 +31 58 01) -- this small cluster of stars was discovered by amateur Matthias Kronberger while visually searching the DSS. It was easily visible at 175x as a small, hazy, granular glow, just 0.8' in diameter. With careful viewing a handful of resolved stars sparkled over the background glow, popping in an out of visibility. Located 4' E of mag 6.4 star HD 190227 and sandwiched between a mag 9 star 1.4' E and a mag 11 star 1.5' W. A number of other brighter stars light up the field.

Patchick 5 (19 19 30.6 +44 45 44) -- I looked for this new planetary along with Dana Patchick, who discovered this object in 2005 by searching the DSS! We were easily able to identify the field using Dana's finder charts and the very faint central star (mag 15-15.5) was seen, but there was no sign of the large, low surface brightness planetary (156"x96"). The central star is located 2.2' SE of a 16" pair of mag 12 stars and 4' ESE of a mag 10 star. Check out Adam Block's image http://www.noao.edu/outreach/aop/observers/ newpn2.html. As far as I know, there have been no amateur sightings, so someone can still claim to be the first to every view this object.

Steve