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Messages - sgottlieb

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1
Observing Reports / Re: Some recent ! and !! doubles, and a question
« on: October 31, 2017, 06:25:43 PM »
I really enjoyed reading your results, Mark!  You've really taken on the challenge of close, unequal doubles.  Great job!!

Are these doubles you ran across using the Interstellarum Deep Sky Atlas or from another source?

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Observing Reports / Re: Observing in Australia October 15-22
« on: October 26, 2017, 11:15:00 PM »
In 1978 I was in full swing with Edmund 6" on a fork mount and did most of the Messiers, but my notes were pretty primitive.  Before that in 1976 I was just poking around the sky with a 60mm refractor in Lafayette.  In the summer I'd point and scan around the Milky Way (yes, there was a Milky Way in Lafayette back then) and "discovered" the showpiece emission nebulae and clusters in Sagittarius and Scorpius.  I thought they were awesome in that little scope.

BTW, I'll post my visual descriptions soon for the entire NGC, but except for the missing 34, they're available now at http://www.astronomy-mall.com/Adventures.In.Deep.Space/steve.ngc.htm

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Observing Reports / Observing in Australia October 15-22
« on: October 26, 2017, 09:28:58 PM »
During the October new moon period I hopped on the 15-hour flight from SFO to attend the week-long Spring OzSky Star Safari (ozsky.org/spring.asp), which took place on the 6300 acre Markdale Homestead (https://tinyurl.com/yd9ju9q5), a 3 to 3 1/2 hour drive west of Sydney in the Central Tablelands (https://en.wikipedia.org/wiki/Central_Tablelands).  I know several TACos have participated in these fantastic star parties (this one was my 4th, out of a total of 8 pilgrimages to the southern hemisphere), but here's the background.

A group of Sydney amateurs, in conjunction with the Three River Foundation (3RF) Australia (www.3rf.com.au/) offer this twice-a-year event, with the main star party hosting 3 dozen or so attendees in the Fall (that's around March-April downunder) at Coonabarabran NSW, near the Warrumbungles National Park and the Siding Springs Observatory.  It's mostly attended by U.S. amateurs and I'd guess half are repeaters, who are itching for more of the same.  What's the draw?  If you've been to the southern hemisphere, you know it beats the north, hands down, in terms of open clusters, globular clusters, emission nebulae and the single most impressive external galaxy in the sky -- the Large Magellanic Cloud.  And experiencing the center of the Milky Way at the zenith (with typical skies ~21.8+ SQM) and the jet-black dark nebulae forming the Aboriginal "Emu in the sky" is flat-out jaw-dropping.

The locals, led by Lachlan McDonald and Tony Buckley, provide the telescopes -- ranging in size from 14.5" to 30" (that's me on the ladder of the 30" on the first link), equipped with Argo Navis and Servocats if you don't want to star hop in unfamiliar skies, as well as a collection of Televue eyepieces.  Really all you need to do to prepare is sign-up in advance, download some of their showpiece observing lists, pack your clothes and join the party!

Two years ago we had a very small, private event.  Only three Californians (John Hoey, Kemer Thomson and myself) attended the Aussie Spring event, which took place at Markdale -- a large working sheep ranch and country estate with a beautiful Heritage garden.  Last October there was closer to 16 attendees, including locals Bob Douglas and Dennis Beckley, but this year we were back to another small group with just 4 U.S. amateurs (a 5th dropped out at the last minute).  That matched the number of scopes that Lachlan carried to the site in his trailer -- two 18's, a 25 and a 30", a one-to-one ratio!  Lodging was in two stone guest cottages, built in the late 1800's.

In mid-October, the galaxy-rich constellations of Fornax, Pisces Austrinus, Sculptor, Phoenix and Horologium pass nearly overhead from Australia and eye-candy galaxies in Pavo, Dorado,  and Reticulum are well placed.  But Sagittarius is still higher than we see it from home, and once you get used to seeing the constellation's Teapot outline completely upside down, its easy to track down obscure globulars and even Sagittarius galaxies that would be difficult from home.  But the biggest treat for me is the LMC, as there is absolutely nothing remotely comparable in the northern sky -- as well as the magnificent globular 47 Tucanae, which must be seen to be believed at high power.

We were pretty fortunate with the weather - 4 straight all-nighters to start the week, then 2 nights of clouds, and a clear 7th night.  So, 5 for 7 overall and enough observing time to log about 250 objects.  I came prepared with a list of 300 deep sky targets, but a subset of 34 NGCs had a special meaning.  These were the only ones I had remaining to observe and record out of the 7840 entries in the 1888 New General Catalogue.  Not sure if the entire catalog (covering +89 to -89 dec) has been attempted or previously completed by other obsessed amateurs. This huge project been percolating a long time -- I've been slowly working on it (along with many others such as Hicksons, Arps, Palomar globulars, Flat galaxies, Abell planetaries, rich galaxy clusters, etc. etc.) for quite awhile -- 37 years to be precise!  And along the way, the instruments evolved from a 6" f/5 Edmund, C-8 Schmidt-Cass, 13.1" Odyssey I, 17.5" Sky Designs (early truss-tube dob), 18" f/4.3 Starmaster and 24" f/3.7 Starstructure, along with a little help from Jimi Lowrey's 48-inch  ;).

Four or five years ago I finished all the NGCs accessible from northern California (down to -40° declination), but there was still over 300 remaining far southern objects.  After a couple more trips to Oz that number was whittled down to 34, of which 32 were well placed this time of year (that's why I missed them a year and a half ago from Coonabarabran).  The final two would have to be caught low in the sky either at dusk or dawn, but I knew they would be doable.  But first a bit of background on the NGC...

Roughly 2500 deep sky objects in the NGC were discovered by musician-turned-astronomer William Herschel from England and another 1700 by his son John, at Slough, England and later the Cape of Good Hope in South Africa.  Their discoveries were made with 18.7-inch speculum reflectors -- roughly equivalent in light-grasp to a modern 14- or 15-inch.  The next largest contributors in terms of visual discoveries were Albert Marth (over 500 using a 48-inch speculum reflector on the island of Malta), Lewis Swift (over 450 galaxies from Rochester, NY and southern CA using a 16-inch Clark refractor) and Edouard Stephan (over 400 from Marseilles using a 31-inch silver-on-glass reflector).  The largest scope that contributed to the NGC was Lord Rosse's 72-inch Leviathan and the discoveries made with this scope go down to mag 16.5V.  Within the next few years after the publication of the NGC, the golden era of visual deep sky discovery would wind down as long-exposure photographic plates revealed thousands of dim galaxies beyond visual reach and which now have IC (Index Catalogue) designations.

During the first two nights I logged 33 of the remaining objects (mostly galaxies in Phoenix and Tucana) using the 25" f/5 Obsession, leaving only one target remaining for the third night -- NGC 2932 -- which is nothing more than a Milky Way star cloud in Vela that captured John Herschel's attention.  He called it "an enormous cluster of 1 deg or 1.5 deg, very rich in stars of all magnitudes, from 8m downwards, which merits registry as a sort of telescope Praesape.  It may be regarded as a detached portion of the milky way."  With so many more mouth-watering targets nearby, most amateurs would probably put NGC 2932 in the "Why bother?" bin. But this one was a little more special to me.

I tracked down the field after 3:00 AM on the third night using an 18-inch Obsession at 79x (1° field of view).  I looked up and noticed Orion was 50° up and of course, turned topsy-turvy on its head!  Sirius and Canopus, the two brightest stars in the sky, hovered at 60° altitude and dominated the eastern skies. Truthfully I didn't find the star field of NGC 2932 very exciting, but I carefully examined it and a 1/4 degree richer section caught my eye as appearing more cluster-like.  The next day I checked the online SIMBAD database and was pleased to find this collection was catalogued as the 1,694th Milky Way cluster in a 2012 compilation (https://tinyurl.com/yb37vzva). So perhaps a real cluster is actually embedded in Herschel's star field.

During the daytime we toured the property, panned for gold, and watched mobs of 'roos bounding across as the fields when we drove by (actually this was a serious road hazard whenever we returned to the estate at twilight) and closely examined some of the other natives (two attached).  A bit scary, though, was a visitor who slithered very close to the observing field in the late afternoon -- an Eastern Brown snake, the second most venomous in the world!  For some false sense of security, I took all of my notes that night (some highlights will follow) at the shelf on the top of a tall ladder, instead of my usual observing table  ;D



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Observing Reports / Re: Lake Sonoma 10/21/17
« on: October 25, 2017, 08:05:14 PM »
Dan's referring to a little project I completed -- more on that later.

5
Observing Reports / Re: Dinosaur Point Saturday night, 21 October
« on: October 25, 2017, 08:04:07 PM »
I'll give a downunder report soon -- always fun seeing Orion rising with standing on its head

6
Observing Reports / Re: Lake Sonoma 10/21/17
« on: October 23, 2017, 07:08:53 PM »
Glad to hear you and Ray are out observing again!  I hope to join you in the next couple of months.

I just got back from the OzSky star party in Australia.  We had 5 clear nights out of 7, so needless to say I'm exhausted and it'll take awhile before entering all my notes.  But I'll post a report as soon as I can.

Steve

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Observing Reports / Re: Globular Cluster hunting -- in Barnard's Galaxy!
« on: August 06, 2017, 03:36:48 PM »
NGC 1049 = Fornax 3 is the brightest globular, then Fornax 4 and 5 a bit smaller and fainter.  Fornax 2 is the faintest of the main 4, which are all visible in a 10-inch or 12-inch.

I would be surprised if you could pick up Fornax 6 as I called it "extremely faint" in the 48-inch, but Uwe Glahn writes that he glimpsed it a 18" from Namibia.  My full description was "extremely faint, small, very low surface brightness spot, ~0.3' diameter.  Located 7' due north of globular Fornax 4.  Pinpointing the location, a mag 15.8 star is 1.6' W and a mag 16.5 star is 2.1' WNW."   But Fornax 6 isn't a globular anyways -- it's either a group of extremely faint stars (~21st mag) or even distant galaxies!

There is a 5th globular, though -- Fornax 1, which is much fainter than the other 4 (perhaps close to 16th mag).  Perhaps this is the one you looked for?

8
Observing Reports / Re: Globular Cluster hunting -- in Barnard's Galaxy!
« on: August 05, 2017, 09:49:00 PM »
For next fall, I was just approved for an observing article in Sky & Tel on Local Group globular clusters, so I certainly hope to get a look at SC 6!

9
Thanks Mark and Marko for the comments and posting the finder chart.  SC 6 is already on my observing list as it's only a 1/2 magnitude fainter than SC 7, but I didn't take a look at Grandview.  Maybe next month.  For the record, here are the coordinates of these two exotic objects.

SC 6   19 45 37.0 -14 41 10.8
SC 7   19 46 00.7 -14 32 35.0

A 2005 study titled "The Globular Cluster System of NGC 6822" (https://arxiv.org/pdf/1506.00951.pdf) gives the following magnitudes (rounded to nearest tenth):

SC 6  15.4V
SC 7  14.8V

Let us know if anyone gives these a try.


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Observing Reports / Globular Cluster hunting -- in Barnard's Galaxy!
« on: July 28, 2017, 06:01:55 PM »
For the July new moon I observed for 4 nights in the White Mountains above Bishop (Grandview Campground at 8500 ft), just below the Ancient Bristlecone Pine Forest.  Our group included Paul and Debbie Alsing, Kemer Thomson, John Hoey (all from the San Diego area), Jimi and Connie Lowrey (from west Texas but drove from Florida) and bay area locals Carter Scholz and Rick Linden.  The weather turned out great and the Detwiler fire southwest of Yosemite didn't impact us, though I drove through the smoke in Yosemite to reach the site.  SQM readings were generally in the 21.6-21.8 range, though occasionally below 21.5.  The largest scope was Rick's 32", which nearly dwarfed my 24" Starstructure.

Instead of posting a long list of observations (I logged 125 objects), I'll mention just one -- a Sagittarius globular that actually resides in Barnard's Galaxy (NGC 6822).  Edwin Hubble was the first to investigate Barnard's Galaxy in detail in 1925 (http://cdsads.u-strasbg.fr/full/1925ApJ....62..409H).  His study included a table of 10 nebulous objects within Barnard's Galaxy.  Most of these turned out to be HII regions (including 2 great visual targets), but Hubble VII turned out to be the first confirmed ancient globular in this galaxy.  The location, though, creates a problem -- its a tiny 16th magnitude speck superimposed on the glow of the galaxy and a very nasty visual target.  I was successful observing it twice from GSSP back in 2010 with my 18", though it was quite challenging (barely non stellar and lost in a maze of other dim stars within the galaxy).  I figured that was the last GC I'd see in Barnard's Galaxy

Four new globular discoveries in this dwarf galaxy were announced in 2011 but these seemed too faint for visual targets.  Then in 2013 three more were identified (so the current total is 8 ) and globular #7 (coincidentally the same number as Hubble's object) seemed a reasonable target for my 24".  When I added it to my observing list, I had no idea what to expect as I've never read of amateur observations of these globulars. You can read the discovery paper at http://adsabs.harvard.edu/abs/2013MNRAS.429.1039H, where it's called SC 7 (Star Cluster 7)

SC 7 is in the outskirts of Barnard's Galaxy, 22' NE of the center of the galaxy and well outside the visual extent -- that makes identification much easier!  Once the general field was centered using the 6mm Delos (375x), both Jimi Lowrey and I were surprised to quickly notice a non-stellar glow without first examining an image of the galaxy.  SC 7 was faint in my 24-inch, but clearly non-stellar, roughly 6"-8" diameter and 15-16th magnitude.  The globular could be held steadily when we backed the magnification down to 282x and possibly had a brighter stellar nucleus.

If you're curious about the distance, Barnard's Galaxy is ~1.6 million light years away.  For comparison, the most distant Milky Way globulars are 300 to 400,000 l.y. away, so this one is at least 4 times that distance!  I believe an 18" scope should catch this object from a dark site, if you know the precise location.

-- Steve 



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Observing Reports / Re: Speaking of subtle...
« on: July 27, 2017, 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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