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Messages - sgottlieb

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1
Observing Reports / Re: Speaking of subtle...
« on: Yesterday at 10:22:09 PM »
Great set of targets, Mark!!

As far as GN 18.32.5 = PNG 27.0 +1.5, it's definitely a planetary neb and not a reflection nebula -- SIMBAD is wrong, wrong, wrong.

Check out this page from the MASH catalogue:  http://vizier.cfa.harvard.edu/viz-bin/vizExec/.show?V/127A&G027.0%2b01.5.  Perhaps I mentioned this one to you before?

I made two observations 9 years back with my 18" ---  I noted the planetary wasn't symmetric around the central star (as you also commented).

18" (7/31/08 and 8/1/08): At 175x unfiltered a mag 13 star was visible and a small ill-defined halo was highly suspected surrounding the star knowing the exact location.  Adding an OIII filter, the halo brightened nicely and the edge sharpened to a 20" disc.  The involved star appeared offset to the north side.

For comparison, here are a few more observations ---

Alvin Huey (22" @184, 255 and 328x): Considerably faint round glow with defined edge with a very bright central star.   Estimated magnitude of the central star is about 11.5.  Not visible without filter.  Ultrablock brings it out pretty well and a similar response with O-III filter.  About 0.5' across.

Kent Wallace (20" @134X and 169X): could see the star superimposed on the northern side of the PN as shown in the SuperCOSMOS blue image. Using the O-III filter and averted vision, a blob forms on the southern side of the star. Good response to the O-III filter. Fair response to the UHC filter. No response to the H-Beta filter. The image is best at 169X. At 254X, the image isn't very good. Identified the field in the AP finder chart. This is a first known visual sighting.

Kent Blackwell (25"): Easy to find because of its involvement with an 11.4 magnitude star.   Even in bright moonlight I could still see it. Once I sighted the nebulosity with the filter I could see it without a filter. It responds so well to the OIII the nebula nearly outshines the involved 11.4 magnitude star.

-- Steve




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Observing Reports / Re: First time Lake Sonoma 7/24/17
« on: July 25, 2017, 07:52:33 PM »
Glad to hear you had a good time at Lake Sonoma.  I've observed there on 150 nights and feel the skies are surprisingly good (generally SQM 21.3-21.45) -- particularly to the west of the meridian -- for so close to the bay area.

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I plan to observe this upcoming week (July 18-22?), along with several other northern and southern California amateurs, at Grandview Campground at 8500 feet in the Pinyon Juniper slopes of the White Mountains, just a half hour paved drive from Big Pine into the Inyo National Forest.  It's roughly a 7 hour drive from Berkeley, but the skies can be magnificent.

If you're interested in more info, contact me at <astrogottlieb at gmail dot com>.


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Rants and Off Topic / Re: Welcome Back Brad Franzella!
« on: July 13, 2017, 08:56:45 AM »
Yep, rain and clouds but we did have one night of viewing -- the first night, which on July 30th (Wednesday).  My notes say I looked at a number of Barnard dark nebulae.  In any case, a lot of fun.

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Observing Reports / Re: Legitimate Peak observations
« on: June 29, 2017, 11:12:11 PM »
Fascinating list of pretty obscure summer targets!  The double to the south of STF 2606 is Ho 290, discovered by Herbert Howe in 1895 with the 20" Clark refractor at the Chamberlin Observatory in Denver.  The current separation is 3.5", which of course is quite easy, but the Delta is 3 mags.  Struve never observed it, but has the designation ADS 13628 (Aitken Double Star catalogue).

I've seen KjPn 1, but not 2 or 3 -- KjPn 2 is listed at V = 17.6 in SIMBAD, which is awfully faint, and I believe KjPn 3 is even fainter.  If you caught these, I'm pretty sure it would be the first visual observations!

Steve

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Equipment Discussions / Re: Help Upgrading Argo Navis firmware?
« on: June 19, 2017, 07:24:09 PM »
I'm also interested in updating my AN firmware, as well as the Servocat firmware.  Has anyone performed this update?

-- Steve

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TAC Visual / Re: Triple double with Cor Caroli
« on: June 19, 2017, 07:20:23 PM »
Cor Caroli was cleanly resolved at 25x using my 80mm finder and even 13x split the pair.  Here's another approach -- what's the lowest magnification to resolve this gorgeous duo?

-- Steve

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Observing Reports / Re: Making the most of it from the Peak
« on: May 31, 2017, 08:33:59 PM »
Perhaps, but it's also possible he misinterpreted some scattered light around the central star as nebulosity.  I've observed LoTr 5 in the 48" and I wouldn't call it a "Very easy object" even in that scope.


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Observing Reports / Re: Making the most of it from the Peak
« on: May 30, 2017, 09:14:44 PM »
Nice set of mostly bright galaxies, but that one planetary -- LoTr 5 -- is a nasty faint shell surrounding a bright central star!

Bob King called it "easy" in this Sky & Tel online article, but I disagree -- http://www.skyandtelescope.com/observing/hunting-giant-planetary-nebulae/

10
TAC Visual / Lake Sonoma OR from Saturday May 20th
« on: May 21, 2017, 01:52:49 PM »
I decided to go to head to Lake Sonoma yesterday afternoon (Saturday) as the predicted conditions were excellent.   Only two others showed up -- Matt Marcus and Shneor Sherman, which was surprising as this was the best weather in terms of temperature/humidity/wind, etc. that we've had in awhile.  It turned out to be a dark night with pretty good seeing.  I made a SQM reading of 21.45, which beats most locations close to the bay area, though the Milky Way wasn't that impressive, so the transparency wasn't ideal.

Unfortunately, we were interrupted for at least an hour and a half by a parade of cars/pick-up trucks that drove into the large Lone Rock lot every few minutes, apparently looking for the rowdy party that took place in the equestrian area just below Lone Rock.  There was also an unusually high amount of road traffic on Rockpile Road, so not a very relaxing evening.  Around 12:30 it finally quieted down and fortunately stayed that way.

One highlight was the type IIP supernova SN 2017eaw in NGC 6946 -- the appropriately named Fireworks Galaxy, which was discovered a week ago on May 14th.  It was easily visible (close to mag 12.5) in the halo of the galaxy, 1.0' west and 2.4' north of the center, and formed a wide pair with a fainter star.  This is the 10th supernova in the past century in the NGC 6946 (I believe I've viewed 4 of these) and it holds the record for the most prolific SN producer: SN 1917A, SN 1939C, SN 1948B, SN 1968D, SN 1969P, SN 1980K, SN 2002hh, SN 2004et, SN 2008S, and now SN 2017eaw.  It may still be on the rise -- in any case it was easy to see in Matt's C-8 and certainly a 6" (or smaller) will do the trick.  Check it out if you view in the next week!!

I also viewed Comet C/2015 V2 (Johnson) in Bootes, which was a bright 7th magnitude (visible in binoculars) and displayed a faint but obvious tail that extended through much of the 13mm Ethos eypeiece field.  It displayed a large coma and an intensely bright nucleus.  This is easy to find and well placed mid-evening, so another one not to miss.

As far as deep-sky objects, I took notes on about 3 dozen galaxies -- mostly working on two projects.  One is to pick up very faint companions to NGC galaxies.  The companions are sometimes in the IC, but often just carry a PGC designation.  The other project is galaxy mergers -- where two nuclei can be resolved within a single common halo.  A good example is NGC 5259, a faint galaxy in Canes Venatici, which I viewed around 1:30.  The second nuclei, labeled in this image as Holmberg 533B (Eric Holmberg studied double galaxies as part of his doctoral thesis in Sweden in the 1930's), was tough at 375x but definitely visible most of the time.

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Observing Intents / OI - Lake Sonoma Saturday 5/20
« on: May 20, 2017, 05:24:20 PM »
I'll be at Lake Sonoma's Lone Rock tonight at sunset for perhaps the last good look at Spring galaxies as they start to slip into the western sky and become less convenient to view.

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Sounds good, I think I'll be there.  ;-)

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TAC Visual / Re: Action on Jupiter
« on: May 03, 2017, 08:33:19 PM »
I missed the reappearance of Europa as I started viewing after the beginning of Io's transit.  I've just kept my 24-inch set up in the driveway and mostly using an 8-inch off-axis mask for an unobstructed view.

On other recents nights (after returning home from 4 nights on the 48-inch), I've been tracking down doubles in Coma Berenices and Canes Venatici, and on Monday night helped put on a public star party for the physics students at Albany High

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TAC Visual / Action on Jupiter
« on: May 03, 2017, 07:58:29 PM »
With the moon now dominating the early evening skies, I've been doing a little Jupiter gazing in my driveway.  On Sunday night, Europa starting transiting the disk of Jupiter around 11:30 and last night (Tuesday) it was Io's turn.  It reached the limb around 10:00 PM and after 10:30, its shadow started marching across the face of Jupiter along the north equatorial belt.  This last sequence of events repeats next Tuesday, though a bit later.

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NGC/IC Project / Re: Corrected NGC v0 online
« on: April 26, 2017, 10:13:02 PM »
I don't believe the NGC/IC Project site ever had labeled images of the IC objects -- or at best a very limited subset.  That said the basic data is available, along with Harold Corwin's identification notes and my visual notes on over 1000 IC objects.

I'll confer with Corwin as well as Akarsh on the easiest way to grab that data.

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