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Distant Galaxies and Clusters

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#151 quazy4quasars

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Posted 02 June 2019 - 08:28 PM

  Yes, Nothing like that Veni, vidi, vici feeling is there?  IC 1101 is a milestone for distance; also the largest Galaxy yet measured. That thing is huge.  Nice sketch too.  bow.gif 
 


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#152 quazy4quasars

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Posted 05 June 2019 - 12:51 PM

 Last night I returned to PGC 60004 - with 30". Happily, after weeks of unsettled weather and fairly lousy sky conditions, the difference in the view was gratifying;  At 360 x it was dim but still direct -in spite of a troublesome 8.4 mag star 2' NNE.   AV gave it a bit more punch and extent and I would occasionally glimpse the AGN lurking within: This sighting was significant as it was local- green zone -about 40-50 miles from a "moderately" large urban corridor- not out at my dark sites.  

 

 For a Galaxy/GX out almost 2.2 G ly, the cosmological dimming and optical continuum downturn may run to perhaps 1.5 mag of surface brightness dimming.  That said, for a quick local view, the <10" ball (blob? clump?) of multiple close, bright cores showed pretty well!  PGC 60004, at z~.183 should be good for at least an easy AV sighting in a big dob under very good to excellent conditions.  Now I want to get out to the desert for a really good look! 

 

 I was also able to glimpse the Double Quasar in Ursa Major, now waaay past its culmination and falling fast:  As I did not have the Tracking system turned on I did not go past 360x. I should have.  Q0957+561 was rather less impressive than I had expected, it was less easy to see the individual components at the same time than it has been in my smaller scopes (under superb conditions) for the most part.  A warm rooftop next door may have been more of a factor than the <45 altitude.  


Edited by quazy4quasars, 06 June 2019 - 12:29 AM.

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#153 sgottlieb

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Posted 06 June 2019 - 04:12 PM

On Monday night (6/3/19), I took another look at PGC 46931 in my 24-inch (I first viewed it last year in Jimi Lowrey's 48-inch).  This is the brightest cluster member of AGC 1738 at z = .115 (light-travel time ~1.5 billion years).   This galaxy is included in the recent Ogle "Super-everything" paper as OGC 99 and was first catalogued by Vorontsov-Velyaminov as MCG +10-19-068.  You'll find it 2.5° north of Mizar at 13 25 11.2 +57 36 01 (J2000).

 

Under SQM 21.4 skies (80+ miles north of San Francisco at Lake Sonoma) it was just visible continuously at 322x as a small, dim fuzz-ball, maybe 12" in diameter.   Timo Karhula was successful using a 12-inch, which is quite impressive.  He mentioned the APASS magnitude is 15.64V, but I believe visually it is closer to V = 14.6 or 14.7.  In any case, it's quite bright for a 1.5 Gly object and definitely a good target for a 16-inch or larger scope in reasonably dark skies.

 

.


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#154 quazy4quasars

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Posted 07 June 2019 - 12:32 PM

  I want to check out PGC 60004 and PGC 46931 in depth- from a real dark sky location, along with some of the more distant OGCs.  I've also come across a z~.3 GX "clump" of cores, not an OGC; that -might- just yield an AV detection:   LEDA 1043019, though that won't be possible till much later in the Summer...        



#155 Redbetter

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Posted 08 June 2019 - 12:47 AM

On Monday night (6/3/19), I took another look at PGC 46931 in my 24-inch (I first viewed it last year in Jimi Lowrey's 48-inch).  This is the brightest cluster member of AGC 1738 at z = .115 (light-travel time ~1.5 billion years).   This galaxy is included in the recent Ogle "Super-everything" paper as OGC 99 and was first catalogued by Vorontsov-Velyaminov as MCG +10-19-068.  You'll find it 2.5° north of Mizar at 13 25 11.2 +57 36 01 (J2000).

 

Under SQM 21.4 skies (80+ miles north of San Francisco at Lake Sonoma) it was just visible continuously at 322x as a small, dim fuzz-ball, maybe 12" in diameter.   Timo Karhula was successful using a 12-inch, which is quite impressive.  He mentioned the APASS magnitude is 15.64V, but I believe visually it is closer to V = 14.6 or 14.7.  In any case, it's quite bright for a 1.5 Gly object and definitely a good target for a 16-inch or larger scope in reasonably dark skies.

 

 

I looked at This one, MCG+10-19-068 (PGC 46931), last night through the 20" in ~21.5 MPSAS conditions.  The seeing was poor and limited me to 227x most of the night, else there were too many very small "galaxy imposters" scattered about.  I would put the galaxy at about 15 mag effective based on the visual impression.  I logged it as:  "found without difficulty, vvF, vs, elongated N/S with average surface brightness, good brightening to middle and vvF stellar core." 

 

I had only penciled the position into Uranometria, so I wasn't prepared with a finder chart to look for other extremely faint companions--and the seeing wouldn't have supported it for the tiny ones nearby.  I did suspect some other galaxies in the area, and even initially found PGC 46930 (MCG+10-19-069) to the north and could see its orientation.  However, for some reason I could not relocate the latter 16+ mag galaxy when I tried to return to it and log it.  Odd, because I was fairly certain of it on the first pass and it served as a marker for the target as well. 

 

PGC 46931 is a very good catch for a 12-inch.  I agree that it should be a good target for a 16" in dark skies.

 

The difficult quarry to locate and see in the same vicinity was UGC 8441 which is even further north.  Unlike PGC 46931, this one is in Uranometria and was found somewhat north of a 14 mag star (I guessed the star as 13 last night)  The 14.5 B mag galaxy's central surface brightness is given as 23.4 B MPSAS.   It is relatively near so somewhat larger in apparent diameter, but very diffuse with only slight brightening to the center.  I listed it as small rather than very small or very, very small which are the norm for galaxies this dim.  I could only tell that it had some generally E/W elongation with some gradual brightening of what I thought to be this main bar/disk, but I could not discern the actual shape.  There was no sign of an actual core other than the slight brightening.  The galaxy is listed as a barred irregular.   I noted a 15/16 mag star following (actually proved, to be a 17.)


Edited by Redbetter, 08 June 2019 - 12:52 AM.

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#156 timokarhula

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Posted 08 June 2019 - 09:45 AM

Great to have this thread still going on!  When I saw the galaxy MCG+10-19-068 (PGC 46931) last April in 2018, I was not aware of its remote distance until a few days after my observation.  It seemed that nobody had ever visually observed this 1.5 billion light years distant galaxy with any instrument at all before me.  The great thing was that I could see this monster galaxy from my back-yard.  And it was not super dark either, my SQM-L showed "only" 21.32.

 

With my 12-inch Dobson, the galaxy was difficult but not extremely difficult.  I was aided by a MegaStar chart when I was actually locating the Herschel-2500 objects NGC5109, NGC5113 and the galaxy IC1875.  I happened to notice the ACO- (AGC-) galaxy cluster ACO 1738 on the same chart so I became very curious and wondered, hmm, that galaxy MCG +10-19-68 might be visible?  The rest of the story is history. :-)

 

/Timo Karhula


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#157 Luca Brasi

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Posted 13 June 2019 - 03:11 PM

timokarhula,
That is my most favorite aspect of viewing the faintest and most distant galaxies available to my 14" scope. There is the possibility that I might be the first person to sketch, or the first to visually detect an object. It is like going where no man has gone before!

Looking forward to my next trip to a Bortle 2 site. Galaxy season isn't over yet... Maybe I'll shoot for a quasar!
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#158 Deep13

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Posted 13 June 2019 - 05:41 PM

My most challenging target was Stephen's Quintet. I barely saw it in my 12.5" Dob from Cherry Springs, PA. I had to tap on the scope, making it wiggle, to be sure I had it.
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#159 timokarhula

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Posted 14 June 2019 - 05:07 AM

Triggered and inspired by my visual observations of very remote galaxies and quasars last year (and years long before), I decided writing an article titled "Far Out" to the Swedish magazine Telescopium published by SAAF (Svensk AmatörAstronomisk Förening = Swedish Association of Amateur Astronomers).  The editors regarded that it should instead be a part of a magazine series of its own called Fokus which deals about some astronomical theme.  Fokus is produced one or two issues every year written by an amateur for the amateur.  This was my second Fokus edition that I had written and the first one was about general visual deep-sky observing which came out in 2014.

 

This week, the booklet was finally distributed to the members of SAAF and it looks quite good with illustrations and search charts in 56 A5-pages.  I had ever since last September researched about how far away you can see planets, moons, comets, stars, nebulae, open star clusters, globular star clusters, details in galaxies, galaxies and quasars with your naked eyes, binoculars, mid-sized telescopes and large telescopes.  Much of the information have I gleaned from threads in Cloudy Nights, thanks to you all.

 

http://www.saaf.se/s...er/telescopium/

 

/Timo Karhula


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#160 quazy4quasars

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Posted 16 June 2019 - 03:38 PM

  Timo, might you be persuaded to offer us Swedish-challenged Yankees a translation of your articles into English?

 

  There really is a feeling of a connection to the infinite- to a timeless continuity, when at the eyepiece I perceive a presence whose lifetime is that of the Universe itself.  Those photons have been streaming silently through the cosmos since forever. any qualification is a quibble -when you see light that has been traveling to your eye since before living things walked upon Earth, or for even longer than the Sun and Moon have graced the night, or eyes have seen,  at the moment of contact. 

 

  I doesn't matter to me who else has seen them or when; as, at that moment they are there in sight, they are mine; I sense again that my little cocoon world is one with the universe, in a very personal way;  immediate; intimate;  yet with a remote and far larger presence, encompassed in time and space with enduring miracle.  I am both smaller and greater, a vital part of a vaster whole.  Our being is a natural expression of the universe, and so I return the favor with my thought.

 

  That connection is just irresistible for me.  When I see such a vista, say the galaxy field of the Coma Cluster; I consider that my scope has transported me to a vantage point where I feel I could almost touch those many many worlds, and in doing so, I feel they have returned a desire of contact -with an incredibly gentle electromagnetic caress, my eye is touched, and I wonder if there are sentient eyes there looking back at us, as well, wondering...  Anyway- Thanks, Universe, you Rock!


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#161 timokarhula

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Posted 19 June 2019 - 05:38 AM

  Timo, might you be persuaded to offer us Swedish-challenged Yankees a translation of your articles into English?

Ok, here you are.  Mind you, this is a machine-translated text from Swedish to English, so I can not guarantee the result. smile.gif   It is the raw text before editing to the booklet Fokus / Telescopium (by SAAF, Swedish Amateur Astronomical Association) and without any illustrations or search-charts.

 

/Timo Karhula

 

Attached File  far_out_eng.txt   27.1KB   19 downloads


Edited by timokarhula, 19 June 2019 - 06:01 AM.

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#162 quazy4quasars

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Posted 18 July 2019 - 12:11 PM

  There were a number of quite distant Galaxies (Super Spirals and BCGs) that I didn't manage to attempt this Spring due to weather and my dark sites being snowed in;  All are low surface brightness and generally they need to be attempted near their culmination, under decently dark skies: Now many are falling into the West; and the Summer -the inner- Milky Way is rising to its late Summer prominence. 

   

  For those who are smitten with the Deep Galaxy bug and want to get a jump on the ones on the other side of the Milky Way, through the Southern Window, I offer this small selection: Some of these are 10-12" and up, others are more like 18-20" class, but dark sky is the main limiter of course:  These are among the most likely visually detectable at such distance; complied from multiple catalogs. You can check CDS, NED, HyperLeda for details:  

 

PGC 188874

PGC 97447
PGC 1480586
PGC 1013135
PGC 71834
PGC 1008418
PGC 97456

 

Fall is coming...Happy hunting!


Edited by quazy4quasars, 18 July 2019 - 12:37 PM.

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#163 SNH

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Posted 01 August 2019 - 04:44 PM

Back on April 30th, CN member Akarsh Simha posted a link to a PDF that Jimi Lowery had made. It was called Chasing Billion Year Old Light and listed all the galaxies in the NGC/IC Catalogs that were beyond one billion light-years distant.
Well, I noticed that at the top of the list were only two galaxies that were beyond two billion light-years – IC 4017 and IC 2657. From looking at a 15’ wide DSS image of IC 2657, I might just have a chance of seeing it in my 10-inch SCT – no joke. But that got me to wondering what might be the brightest galaxy that breaks the two billion light-year mark. Is it IC 2657?

 

Any help would be greatly appreciated!

 

Scott


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#164 quazy4quasars

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Posted 01 August 2019 - 05:14 PM

Back on April 30th, CN member Akarsh Simha posted a link to a PDF that Jimi Lowery had made. It was called Chasing Billion Year Old Light and listed all the galaxies in the NGC/IC Catalogs that were beyond one billion light-years distant.
Well, I noticed that at the top of the list were only two galaxies that were beyond two billion light-years – IC 4017 and IC 2657. From looking at a 15’ wide DSS image of IC 2657, I might just have a chance of seeing it in my 10-inch SCT – no joke. But that got me to wondering what might be the brightest galaxy that breaks the two billion light-year mark. Is it IC 2657?

 

Any help would be greatly appreciated!

 

Scott

My many catalog searches have led me to conclude it is the brightest for that distance - but not by much.  There's a couple more that are in the ballpark for overall magnitude, and their cores are what may make or break a detection in 10".  Let us know how you do! 

 

Okay,  OGC 0039    2MASX J17120987+6143147  A bit more luminous but also a bit further out (z~.172)  However, MUCH better placed for viewing right now:  core larger but less intense.  (based on SDSS, Pan-STARRS g imagery)

 

PGC 60004 leaps to mind as well!   17 17 19.210 +42 26 59.84  but there's an 8.4 mag star 2 arcmin away.


Edited by quazy4quasars, 01 August 2019 - 05:21 PM.

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#165 SNH

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Posted 06 August 2019 - 11:26 AM

Thanks for that Q4Q! I looked and 2MASX J17120987+6143147 is a touch dimmer than IC 2657. PGC 60004 is mysterious because it looks a little square for a galaxy but some sources list it as a quasar! Hmmmm.

To be able to view such faint objects in my "little" telescope, I need the best, most transparent skies over my home and that only happens from October through April. But I've got to get the objects that I want to look at then figured out ahead of time, so I'm starting always!

 

Scott



#166 quazy4quasars

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Posted 06 August 2019 - 12:20 PM

Thanks for that Q4Q! I looked and 2MASX J17120987+6143147 is a touch dimmer than IC 2657. PGC 60004 is mysterious because it looks a little square for a galaxy but some sources list it as a quasar! Hmmmm.

To be able to view such faint objects in my "little" telescope, I need the best, most transparent skies over my home and that only happens from October through April. But I've got to get the objects that I want to look at then figured out ahead of time, so I'm starting always!

 

Scott

Ogle Gives 2MASX J17120987+6143147 (OGC 0039)  as  15.5  L*  (L* = Milky Way luminosity);  whereas  IC2657 (OGC 0134) is given 12.1 L*.  In imagery, IC2657 has the more intense core,  but 2MASX J17120987+6143147 appears larger, in spite of its slightly greater distance; so it might come down to seeing vs transparency as to which is more detectable,  -also,  IC 2657 is done for the "season" , whereas 2MASX J17120987+6143147  is well placed in the N evening sky.  (and while you're "there", maybe try for QSO  3c351, a 4 Gly QSO, mag V~15.3) Both galaxies will be very challenging in 10".

 

PGC 60004 (OGC 0022) does contain an AGN - that helps the (a little more) distant BCG-blob to stimulate those rods, no doubt.  In my 17.5", it is the blob, clearly non-stellar, that is just direct-visible in good, dark conditions.  The AGN glimmered in and out in my 25", within the visible GX,  If you see anything non-stellar at the position, you will be seeing the GX.  It looks like the faint ghost of a gibbous Moon to me.  Best of luck.


Edited by quazy4quasars, 06 August 2019 - 12:43 PM.


#167 SNH

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Posted 06 August 2019 - 12:43 PM

Ogle Gives 2MASX J17120987+6143147 (OGC 0039)  as  15.5  L*  (L* = Milky Way luminosity);  whereas  IC2657 (OGC 0134) is given 12.1 L*.  In imagery, IC2657 has the more intense core,  but 2MASX J17120987+6143147 appears larger, in spite of its slightly greater distance; so it might come down to seeing vs transparency as to which is more detectable,  -also,  IC 2657 is done for the "season" , whereas 2MASX J17120987+6143147  is well placed in the N evening sky.  (and while you're "there", maybe try for QSO  3c351, a 4 Gly QSO, mag V~15.3)

 

PGC 60004 (OGC 0022) does contain an AGN - that helps the (a little more) distant BCG-blob to stimulate those rods, no doubt.  In my 17.5", it is the blob, clearly non-stellar, that is just direct-visible in good, dark conditions.  The AGN glimmered in and out in my 25", within the visible GX,  If you see anything non-stellar at the position, you will be seeing the GX.  It looks like the faint ghost of a gibbous Moon to me.  Best of luck.

Okay, good to know!

 

Scott



#168 sgottlieb

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Posted 06 August 2019 - 05:33 PM

For comparison of these two OGC galaxies at 2+ billion light years, I observed PGC 60004 (z = .183) and 2MASX J17120987+6143147 (z = .173) consecutively at the Golden State Star Party just a month ago.  For what it's worth, I logged PGC 60004 as "very faint" but visible continuously" at 450x in my 24", but 2MASX J17120987+6143147 = LEDA 2623325 appeared "extremely faint" and only visible intermittently.  So, PGC 60004 was definitely an easier target!

 

There's an fascinating paper on PGC 60004 published in 2017 by Condon et al  titled "A nearly naked supermassive black hole"

 

From the abstract:

"During a systematic search for supermassive black holes (SMBHs) not in galactic nuclei, we identified the compact symmetric radio source B3 1715+425 with an emission-line galaxy offset ≈ 8.5 kpc from the nucleus of the brightest cluster galaxy (BCG) in the redshift z = 0.1754 cluster ZwCl 8193. B3 1715+425 is too bright and too luminous to be powered by anything but a SMBH, but its host galaxy is much smaller and optically fainter than any other radio galaxy. Its high radial velocity vr ≈ 1860 km/s relative to the BCG, continuous ionized wake extending back to the BCG nucleus, and surrounding debris indicate that the radio galaxy was tidally shredded passing through the BCG core, leaving a nearly naked supermassive black hole fleeing from the BCG with space velocity v ≥ 2000 km/s"

 

On page 4 of the paper there's a deep HST image of PGC 60004 showing its full extent, along with gravitationally lensed background galaxies, and a shorter exposure below that pinpoints the emission-line galaxy (radio source B3 1715+425) with what the authors describe as a "nearly naked SMBH"


Edited by sgottlieb, 06 August 2019 - 05:35 PM.

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#169 quazy4quasars

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Posted 15 August 2019 - 07:50 PM

imgcut (33)PGC_60004.jpg   Here's the crux;  2MASX J17120987+6143147  and  IC2657 are both single, highly luminous BCGs;   PGC 60004 is not a single Galaxy but a tight clump (or partly a line-of-sight alignment?) of a BCG and several other cD Galaxies, including the AGN core of the cD galaxy that was stripped by its passage through the BCG.    

 

  SDSS and Pan-STARRS imgery show multiple dense cores appearing within the common envelope, so PGC 60004 may be more properly described as a Galaxy Cluster (specifically;  ZwCl 8193 ), perhaps as a Northern analogue to Abell 3827 in the far South, or the deeper and even more difficult Abell 1835 in Virgo, which also hosts a quasar.  

 

  The combined light of the BCG; several cD Galaxies and an AGN do make PGC 60004 an easier target, but I don't really consider it a single BCG, as IC2657 and 2MASX J17120987+6143147 are, in spite of its OGC designation (OGC 0022).  I think of it as a galaxy glob!   CDS gives V~16.0,  z~.1829, -over 2.2 Billion light years, out in the realm of the quasars.  


Edited by quazy4quasars, 15 August 2019 - 08:04 PM.

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#170 Luca Brasi

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Posted 07 September 2019 - 10:58 AM

Going for the 2 billion mark!  Oh my!

Camping season is over here in Colorado, just had our first snow.  So I'm stuck doing Bortle 3 observations and IC1101 took every observation trick I had to see in Bortle 2.

 

Maybe my eyepieces have too much glass?  What eyepieces have you all been using for 1-2 billion light year objects?



#171 quazy4quasars

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Posted 07 September 2019 - 12:06 PM

Going for the 2 billion mark!  Oh my!

Camping season is over here in Colorado, just had our first snow.  So I'm stuck doing Bortle 3 observations and IC1101 took every observation trick I had to see in Bortle 2.

 

Maybe my eyepieces have too much glass?  What eyepieces have you all been using for 1-2 billion light year objects?

Most of mine are type 2 Naglers,  but it's more about catching these Galaxies near their culmination, because they are low surface brightness sources to begin with, particularly as you get closer to 2 Billion light years.  Full dark adaption is a must, of course, and you'll be upping the magnification to minimize the field brightness.  Begin with medium power:  your ES14 for example, and then go higher:  My scopes are f/4.5 -f/5 and I find a 9mm or a 7mm get me the best views.  The super wide field doesn't help;  rather you may want to back your eye away from the eyepiece to "aperture out" more of the field. Also, averted vision is your friend!

 

It's a trade off between magnification and contrast so there's no single ideal eyepiece, its whatever works best for your eye and your sky. You'll still be able to try for PGC 60004 west of the zenith after the next full moon.  If you have a Plossl around 8 to 10 mm, you might want to try that, for a comparison, but the contrast difference due to glass should be nearly zero.


Edited by quazy4quasars, 07 September 2019 - 12:14 PM.


#172 Luca Brasi

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Posted 07 September 2019 - 10:07 PM

I've been considering getting another 7mm Nagler.  My 9mm 120 degree is just to much for such faint objects and my 5.5mm is just on the edge of being too small of exit pupil.  I really miss my 7mm Nagler.  That eyepiece/exit pupil was perfect for the small faint fuzzies.  

 

But don't get me wrong, that 9mm 120 degree is pretty amazing on the brighter Abell clusters.  The Coma Cluster from Southern Utah was one of my lives great moments.  It felt like I was like swimming through the cosmos!


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#173 Redbetter

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Posted 07 September 2019 - 10:52 PM

I use Naglers, typically 9T6 or 7T1 and if the seeing is good enough and the target small enough, a 5T6 or 3-6 TV zoom for the most distant targets at 2 to 3 billion light years.  I could probably use an 8mm...there are times when going from the 9 to the 7 is a little beyond what conditions really support. 


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#174 NGC7702

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Posted 08 September 2019 - 01:04 AM

Hi All,

In terms of "normal" galaxies (ie not QSOs) a possible target for southern hemisphere observers with very large telescopes is ESO 146-8 near the Indus/Tucana border. I haven't had a crack at it as yet but will do so in the next couple of months with my 25" f/5. It has a nice set of nearby marker stars that should make identification of the precise location pretty easy. My observing site in central NSW, Australia typically has SQM-L readings near zenith of about 21.7 - 21.8 this time of year on moonless nights. Even so, I think it would be pushing the edge of the envelope.

ESO 146-8 has a B mag of +16.7  coupled with V(km/s) +48400 [~] / z(~) 0.176884 [~] implying a look-back time in the order of 2.2 Gyr (assuming a Hubble constant of 71.5 kms/sec/Mpc).

http://simbad.u-stra...ubmit=submit id

It is found only a couple of high-power fields away from the somewhat brighter but still very distant ESO 146-5 (I have seen ESO 146-5 in my 18" f/4.9) that has a B mag of 15.75, V(km/s) +28711 [99] / z(~) 0.10083 [0.00033] and therefore resides probably about the 1.3 Gyr look-back time.

http://simbad.u-stra...ubmit=submit id

 

 

Best,

L.


Edited by NGC7702, 08 September 2019 - 01:28 AM.

  • timokarhula likes this

#175 quazy4quasars

quazy4quasars

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Posted 08 September 2019 - 04:21 PM

I use Naglers, typically 9T6 or 7T1 and if the seeing is good enough and the target small enough, a 5T6 or 3-6 TV zoom for the most distant targets at 2 to 3 billion light years.  I could probably use an 8mm...there are times when going from the 9 to the 7 is a little beyond what conditions really support. 

 

Redbetter, you enjoy better conditions than I do, even at my high altitude sites-  Which would you consider to be the "easiest" of the extreme (Not QSO) galaxies out closer to 3 Gly than Abell 2261BCG (as if any could be considered easy!)?

 

 Even my 25" with enhanced Aluminum mirrors will never make them "bright", but I'd  ~hope~ to avoid the "barely visible in averted vision less than half the time" scenario, short of driving to the middle of Nevada.  grin.gif




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