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azure1961p
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Nice views of Uranus and Neptune (Finally)
      #6108481 - 09/30/13 12:13 AM

9.29.13
10:45pm EDT
Seeing : 5-7 Pickering
Transp: a little smooth high altitude haze
Temp: 60f

NEPTUNE...
A very fair view (finally) that up to this point proved often too soft to stand higher magnifications. Here I got a nice 7 Pickering and best overall view at 303x. A tight slate blue pale green orb as it drifted across my undriven dob FOV. It took 450x to see Triton with certainty as transparency isn't great tonight, but the planet again was best at 303x..

Its sobering just how exceedingly minute this planet is at 70x. Its such a close call.



URANUS...
It was easy navigating to this brighter bigger object after having been back and fourth with Neptune the last 6 weeks. It was the best view Ive had in a while...

The face was a perfectly blank warm shade of wooly grey blue. The warmth is that pale yellow in the blue. Calling it green is an overstatement .
I found like Neptune that 303x tonight was a fair magnification. The seeing smeared it often but just the same it would reconstitute and be a tight sharp pale warm blue grey orb. It had a powdery texture. Though I saw no details I wouldn't call this a conclusive view in possibilities of seeing something on a better night.

Moons were out of the question - seeing had OK periods but the transparency while not awful, was poor.

Wrap up: Two very nice proper views of the two outter giants. Reading Schmudes book further enhances the observing experience. Some folks are let down by these two but I find their challenging nature very engaging .

Scroll down for finished renderings of both planets and Triton.


Pete

Edited by azure1961p (09/30/13 04:58 PM)


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Asbytec
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Re: Nice views of Uranus and Neptune (Finally) new [Re: azure1961p]
      #6108607 - 09/30/13 02:18 AM

Pete, great to see you out in the elements doing it. It is fun.

I'm seeing some color variations in both swatches, is Uranus north to the left? (Kidding.) Is Neptune really that dark?


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CPellier
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Re: Nice views of Uranus and Neptune (Finally) new [Re: Asbytec]
      #6108689 - 09/30/13 05:17 AM

Hi Pete,
Nice observations. It's really fascinating to observe those planets...
Regarding the color of Uranus, you may not be able to see the green color if your telescope is a 8" (if I look in your signature). When I was observing with a 7" newtonian many years ago, even under a dark sky the color remained pale blue to me. It was only when I got a 10" that the green tint became accessible.
More over, this depends as well on the sky transparency. With my 10", I do not see the green through my urban sky - the planet is almost grey. But with the same telescope used in the country, the green is visible.
Last summer at the eyepiece of the 620 mm cassegrain of Astroqueyras at an altitude of 3000 meters, the color was very pale green, almost white (!) and absolutely no blue, while Neptune was clearly sky blue.
(of course we may have some differences in our eyes, yet it is curious that observers disagree only about Uranus !)


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azure1961p
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Re: Nice views of Uranus and Neptune (Finally) new [Re: CPellier]
      #6108913 - 09/30/13 09:25 AM

Hi Guys,


Yes Norme the Neptune image is a little dark . It'd be easier if it were illustrated on a dark background but I did all the editing here on my phone!
Ill probably rework it today. Ill be putting out a finished digital sketch of Neptune and Triton later as well - though not edited with my phone.

Mr. Pellier - thanks for the accounts on your behalf. I completely agree that a darker sky has an impact on how well we perceive color. I find viewing from my condo with all the extraneous light from every angle plus the urban light dome really mutes the colors - particularly on Neptune. From a darker country sky there is this blue/teal that's unique and unmistakeable - but here from the city its merely blue with the barest suggestion of green element. Uranus is a planet Ive never seen through a large instrument but I don't doubt the added light and scale would help that green shine in through. A curious thing is my childhood view if Uranus. I stumbled upon it accidentally with a 4.25" reflector. It mystified me - i had no idea what i was seeing - more over that it defied substantial enlargement similarly vexed me. What I recall vividly still though is the color. Chris to my. 14 year old eyes it was a pale grey with lime green tinges. I had no pre suggestion here - I went to bed that night not knowing what the heck it really was. All that to say I believe the age of 52 has taken away some of the color sensitivity of 14! I later used a planetarium program to the date and time ( approx) and sure enough it was Uranus. How I chanced upon it is pure dumb luck. I think the low power color must've caught me. At anyrate - I agree with your finds - I look forward to a large aperture view one day - and the seeing to realize it.

I noticed color comes in pulses or bursts with small orbs like Titan and these outter two. The tinged of color would pop up almost like morse code sequence then fall back to muddled grey. I'm guessing the off and on pulses of color reception are the cells of seeing focusing and defocusing the light hence the way it would reconstitute in a series of subtle flashes.


Pete


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azure1961p
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Re: Nice views of Uranus and Neptune (Finally) new [Re: azure1961p]
      #6109104 - 09/30/13 11:39 AM Attachment (50 downloads)

Here's the finished sketch of Uranus - I thought I caught glimpses of Titania but its beyond the size of the rendering. The colors are about optimum for what I saw visually from this location.

Pete

Edited by azure1961p (09/30/13 11:44 AM)


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azure1961p
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Re: Nice views of Uranus and Neptune (Finally) new [Re: azure1961p]
      #6109109 - 09/30/13 11:41 AM Attachment (37 downloads)

And Neptune with dim Triton preceding it. It was essentially invisible due to thin haze and required. 450 x over 303x to make the catch.

Pete

Edited by azure1961p (10/03/13 04:50 AM)


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Jon_Doh
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Re: Nice views of Uranus and Neptune (Finally) new [Re: azure1961p]
      #6109145 - 09/30/13 11:55 AM

That's incredible for an 8 inch scope. I have an 8 inch SCT and I can never see more than a pinpoint.

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azure1961p
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Re: Nice views of Uranus and Neptune (Finally) new [Re: Jon_Doh]
      #6109377 - 09/30/13 02:41 PM

Well it's never as large as its drawn, but between 250x and 450x is a discernible disc that's clearly beyond a point. A C8 on a good night (took me long enough) ought to show it well if you can get between 300x - 400x.

Thanks!

Pete


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Jon_Doh
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Re: Nice views of Uranus and Neptune (Finally) new [Re: azure1961p]
      #6109590 - 09/30/13 04:38 PM

Thanks Pete. I 'll try cranking up the magnification next time I'm out and see if that helps.

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bherv
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Re: Nice views of Uranus and Neptune (Finally) new [Re: azure1961p]
      #6109859 - 09/30/13 07:36 PM

Saturday night we had pretty good seeing conditions here in the northeast. I was using the club's 17.5" and was able to see both Oberon and Titania quite clearly. I have never been able to see them before.
Barry


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Ed D
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Re: Nice views of Uranus and Neptune (Finally) new [Re: bherv]
      #6109968 - 09/30/13 08:32 PM

Pete, beautiful sketches. I know you had been posting about the bad weather up there. Glad you're finally getting to observe.

Ed D


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mark8888
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Re: Nice views of Uranus and Neptune (Finally) new [Re: Ed D]
      #6111079 - 10/01/13 12:01 PM

Awesome report about 2 great planets, thanks. I havent been able to see them thus far this season but will do. Viewing Neptune and Uranus always gives me a unique "I'm hanging out on the edge of the solar system" feeling... very cool and actually spooky.

( kinda related spooky article here (voyager 1 has since left the solar system) )


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David Gray
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Re: Nice views of Uranus and Neptune (Finally) new [Re: azure1961p]
      #6112577 - 10/02/13 07:52 AM


Pete I feel you have got some pretty near colours for these two planets.

I have to say over the years Neptune has fairly consistently looked to me quite strongly blue, a little more greyish at times. But have often been perplexed by the hues that Uranus has presented. All the way from sky blue to almost yellow. These past apparitions with it getting higher in my skies I see more of cyan, tending more green-ward at times: so yellows might come from low altitude reddening. In fact I reckon that the colours used in the WinJUPOS simulations are pretty good representations for both planets on the whole – at least for my impressions of late.

When I started systematic observing of Uranus back in 1969 March (10” f/8 Newtonian) I was getting striking differences night to night. Often looking quite green; then another night almost sky-blue. Intriguingly when it looked green I was getting faint banding (plus limb shading), in the best seeing, and in equally good conditions it looking sky-blue and quite blank apart from limb shading.

Looking back then I was using a red light (which I always found uncomfortable and abandoned for good in 1970 – preferring ‘white’) and have often wondered if the common use of red is behind a lot of the green hues perceived by others. A pity I have no record of which of those nights I had the red light on….! But the planet is back higher and an experiment is easily set up.

Back in 2007 James Bryan (Texas Uni.) sent me a paper by the late Peter J. Young, an accomplished UK observer, who described his experiences with both planets. He used the following instruments (1974 & 1976): 9” refractor, 12” (Northumberland/Cambridge) refractor, the 36” & 82” reflectors at McDonald Observatory Texas. He had these comments re. their colours - Uranus: “The colour of the disc in the large apertures would best be described as creamy-grey with only a vague hint of yellow or green; the hue is less pronounced in the luminous images of the large reflectors than in the small refractor.” Neptune: “Again the colour was not as pronounced as in the small refractor, best being described as cold grey, different from the creamy grey of Uranus.”

Uranus in particular might well be accentuating individual differences with colour perception??

David.

Edited by David Gray (10/02/13 07:57 AM)


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CPellier
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Re: Nice views of Uranus and Neptune (Finally) new [Re: David Gray]
      #6113679 - 10/02/13 06:10 PM

David, very interesting testimonies that are quite coherent with my first experience with a very large aperture last summer (620 mm cassegrain). Uranus was very clear, almost white, although I still evaluate the basic color as greenish. But "creamy grey" is not that far. Here is the image processed from my visual impressions.
What was surprising is that the color was actually less intense than what I see through my 250 mm. I would have expected the opposite....
Neptune's color was more easy to catch in comparison. Just pale blue.



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azure1961p
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Re: Nice views of Uranus and Neptune (Finally) new [Re: CPellier]
      #6114231 - 10/02/13 10:34 PM Attachment (22 downloads)

Hi guys,

David, I am always surprised at how susceptible color in small apparent orbs like Uranus and Neptune ( Ill add Titan and Io in there too) can be to changes in seeing conditions. That Uranus had shown a different hue when sharp and revealing bands is a nice example of how it resaturates its color from periods of lesser seeing. What's so curious about these things to me is that had I a micrometer to measure the soft focus compared to the sharper focused orb itd be a very close measurement - quite fractional even. But for my eyes anyway its the difference between seeing neutral plain grey and specific color. Lesser seeing seems to desaturate.

What's interesting about the larger apertures showing less color than smaller is that it seems to echo the effects of color with doublestars where a medium aperture might show a nice crimson carbon star tinge while a very large aperture turns it a rusty orange and that snazzy cherry color is lost totally. Perhaps these larger reflectors are bleaching retinal sensitivety and paling some of the colors if not appearing to shift them outright.

The low altitude reddening by the way is an interesting notion . A low altitude Jupiter to me will have a creamy appearance - it'd make send that Uranus would as well. infact, the yellowest I saw Uranus (when I was 14 as mentioned elsewhere) the color was a dead ringer for Christophes Uranus . I had often believed, lamentably, this was an age thing where my 52 yr old eyes can't match my youths even though Ive doubled my aperture. Looking back on it though, it was no more than 25 degrees off the horizon - I had to look through tree branches across the yard. Maybe Ive put too much blame on age?

Thanks for the comments and accounts.

Attached for comparison is the color Ive sen under dark country sky's without the intrusion of lights etc. Itd have this color surface out of the grey that was beautiful actually and unlike Uranus though still, dimmer of course. That blue green under dark sky's and no glare is a very fine sight.
This was a fleeting though reoccuring tinge - the pic makes it seem rather plainer than it actually was.

Pete

Edited by azure1961p (10/02/13 11:22 PM)


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E_Look
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Re: Nice views of Uranus and Neptune (Finally) new [Re: azure1961p]
      #6114368 - 10/02/13 11:55 PM

I am very happy for you Pete that you finally got in a very nice session on these two planets, including Triton!

Funny thing, and I think I've posted this before, but at low powers, Uranus looks almost lime green to me, the blueness not registering until I raise magnification. Neptune always seems blue to some level at any power.


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stanislas-jean
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Re: Nice views of Uranus and Neptune (Finally) new [Re: CPellier]
      #6114468 - 10/03/13 01:50 AM

If I may add something on this coloring Uranus aspect,
presently this opposition the planet appears to be creamy-litgh yellow greyish in the 280mm and more greenish in the 127-180mm. Last opposition the coloring was according my observation more greenish.
It seems variating from an opposition to an other and I think our personnal eyes may get different aspect with regards to own eye sensitivity to some color channel.
But these considerations are not coming from photometric measurements.
Stanislas-Jean


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David Knisely
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Re: Nice views of Uranus and Neptune (Finally) new [Re: CPellier]
      #6114544 - 10/03/13 03:58 AM Attachment (22 downloads)

To me, Uranus has always been a sort of pale sky-blue with maybe only the faintest hint of green. Below is a rough approximation of the color, although it is a little more saturated that when I am actually viewing it.

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azure1961p
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Re: Nice views of Uranus and Neptune (Finally) new [Re: David Knisely]
      #6114558 - 10/03/13 04:54 AM

Nice sketch Dave. I think its kind of had to make a static image of true color representation on the outter planets sometimes because the seeing and color sensitivety of the eye can be so fleeting at times. Deepsky drawings seem to be particularly subject to this especially when you factor in the elusive quality of averted vision. Alas its the sum of the observing experience.

Nice work.

Pete

Edited by azure1961p (10/03/13 05:35 AM)


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David Gray
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Re: Nice views of Uranus and Neptune (Finally) new [Re: azure1961p]
      #6114597 - 10/03/13 06:07 AM

I tended to suspect that Young’s Uranus colour impressions with the large reflectors was due to brightness/bleaching ‘whiteout’. Neptune being fainter not so affected I would think. I am getting some of this (especially non-binoviewer) recent apparitions as Uranus gets higher each year. But at the same time I recall conversation with Richard McKim regarding Mars & Saturn in large scopes (Pic, Meudon,) as showing a rich palette of hues, and he related similar comments by de Vaucouleurs with Mars.

I have taken issue in the past when certain popularisers wax lyrical about blood-red Mars (and Betelgeuse etc); and have to say if they have blood that colour they need medical attention and would be surprised to see them walking about!

How colours are perceived depends a lot on what we have been looking at just previously to the object in view. During some colour investigations with Titan’s redness I selected a number of similarly bright G,K&M, near-field, stars for comparison. As I thought at times Titan was even rivalling some carbon stars I decided to include some, and found, then, nearby SS Vir – this soon showed me it was way redder than Titan! However I was so charmed by the star’s hue I spent some time just looking at it (415mm/16.3” D-K) – was about mag. 7. Just after that Mars caught my eye toward the west and after SS Vir it looked nothing more than pure yellow (n. eye) and it took some 20 mins. to ‘normalise’.

Further during that investigation Titan made a very close approach to a K star that at first looked more orange than Titan; then as they closed a most peculiar complementary ‘double-star’ effect became increasingly marked. Titan started to look the redder then when they got to c. 15” Titan took on the most strange dull brick-red cast and the star looking little changed – very curious.

These past years I have spent a lot of my observing trying to represent colours I see on planets etc on the computer. Before going on I would like to stress that what I depict is not an attempt (futile!) at absolute/true colour; but simply as I see them. This has taught me much as to how colours are affected against each other. Difficult with art media: the PC allows fine tweaking one shade adjacent to the other/s. For instance some years back I was getting a broad dusky band on Uranus that often conveyed a warm brownish tendency. Had I been using pastels I would probably have applied a grey with a touch of terra cotta. The PC revealed this to be way off (against the general hue) – garish even; and by I had tweaked it to satisfaction the Corel Photopaint colour-sampler revealed it to be a pale olive-brown – regardless of whether it was subjective/real or not in the eyepiece.

Of course how I see colours on my monitor/s probably differs with others – and that is a another can of worms! Once at a family gathering we had my two desktops and four laptops all set to default as an experiment, and we viewed some of my colour drawings on ALPO-J – and they all looked different: colour-wise and contrast & brightness too…..!! Some really dreadful to me!

I should point out that my various colour differences with Uranus were very much in comparable ideal to excellent conditions, In particular I stress that I resist doing drawings of any planet if the seeing is not better than III (5/10): for Uranus, Neptune & Venus no worse than II-III (6/10 – 7/10). Unless some ‘extreme’ phenomenon was apparently ‘poking’ through the turbulence – then an impressionistic drawing would be executed; with appropriate notes.

Ageing eyes: Walter Scott Houston often touched on this in his S&T Deep Sky Wonders. In particular with yellowing of the eye-lens. Which he also put down to smoking, and I’ve seen photos of him with a pipe…!! He used to offer as a test certain planetary nebulae that tended to look bluer to younger eyes and more green to older ones.

I’m 69 and a non-smoker all my life and pretty happy that any yellowing is very minimal – if any. Vega, brighter Pleiades, Orion belt stars all striking blue to me; not greenish or even yellow that some would be saying I’d be seeing at my age. Back in the mid 1960s I used to enjoy the sky-blue hues of NGC 6210 & 6572 and have often revisited them over the years; most recently when I still saw no green in 6210 with 6572 very slightly so – both these have a superficial resemblance to Uranus to me and could ascribe either’s colours to it at various times.

Could go on (lots of worms in the cans) but better stop perhaps other points some other time.....!

I am hoping to put a graphic-type illustration on the Sketching Forum of the colour changes in Nova Del against it's light-curve and included carbon star X Sge. Maybe on soon but hoping the weather forecast is right for the weekend and allows me to add more before posting.

David.


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azure1961p
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Re: Nice views of Uranus and Neptune (Finally) new [Re: David Gray]
      #6114747 - 10/03/13 09:12 AM

As I recall, Walter in his later years finally had a cornea transplant and upon receiving the new lens, the yellow was gone. It was that or a cataract but at anyrate he noticed that greenish stars turned back to blue.

Pete

Edited by azure1961p (10/03/13 12:39 PM)


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David Gray
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Re: Nice views of Uranus and Neptune (Finally) new [Re: azure1961p]
      #6114787 - 10/03/13 09:38 AM

Yes that's right!! Thanks for refreshing my memory.

All sorts keep coming to mind lately from those old S&Ts: keep meaning to get them (100s/jumbled ) back in proper sequence and go through them!

Cheers,
Dave.


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ericj
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Re: Nice views of Uranus and Neptune (Finally) new [Re: azure1961p]
      #6114992 - 10/03/13 11:45 AM

Very fine observing reports and sketches Pete, you recorded some nice detail,

Best,

Eric


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Jon_Doh
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Re: Nice views of Uranus and Neptune (Finally) new [Re: David Gray]
      #6118734 - 10/05/13 10:07 AM

Finally got a good view of Uranus last night. With an ES 6.7 82 deg eyepiece it looked a lot like the picture in David's post, except that it was a bit more gray and less blue. I stayed at the eyepiece for a long time enjoying the view and then trying it with an 11mm, the 11 with a barlow and the 6.7 with a barlow (too dim and fuzzy). Was just simply amazing.

Next, I slewed over to Neptune and there it was too. Much smaller than Uranus even at high magnification, but still a sight to behold - for me since I had never seen it anything more than a pinpoint. It was sitting there as a solid round little disk.


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azure1961p
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Re: Nice views of Uranus and Neptune (Finally) new [Re: Jon_Doh]
      #6119003 - 10/05/13 12:49 PM

Hi Jon,

Nice report. You might want to try the Galilean moons next when Jupiter rises to height at an hour you agree with. Even in mediocre seeing every moon subtends a discrete disc at 200x or more and 350x is superb. The latter magnification from my experience needs 7/10 or better seeing. Pretty rare last winter. Titan's another one that subtends a true disc . When the seeing complies 8" can go way down to extremely minute orbs.

I enjoyed your account Jon.

Pete


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Jon_Doh
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Re: Nice views of Uranus and Neptune (Finally) new [Re: azure1961p]
      #6120219 - 10/06/13 09:09 AM

Thanks Pete.

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aa6ww
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Re: Nice views of Uranus and Neptune (Finally) new [Re: Jon_Doh]
      #6125245 - 10/08/13 03:44 PM

Saturday night 10-5-2013, I had a nice view of the Planet Uranus with my C14. The seeing conditions were perfect at 5/5, and transparency also. I was out at a small town near where I live, in Wilton Calif. Its in the Orange zone. At about 435x with my 9mm Nagler, I noticed two small moons above the planet in the 11 o clock and 1 o clock position from Uranus. At 558x, using my 7mm Nagler, a few more very tiny moons were starting to come through, even closer to the planet than these two, but they were in and out and in the glow of Uranus. I don't recall the names of these moons. Later on, I checked and Stellarium was showing the first two moons as Oberon to the right, and Titania to the left. One was at mag 14.93, the other at 14.63. I don't recall the names of the other moons but they were in the 15.6 mag range. I was impressed I was able to see glimpses of these dimmer moons but again, they were in and out and I really had to look at them with a dark cloth over my head to really concentrate on what i was seeing.
The planet itself was spectacular. One of my friends said he had never seen the planet so large and vivid ever.
One of the web sites, i think it was Astrobob, was stating that Oberon and Titania were going to be visible this weekend, because Uranus was at opposition from Earth at this time. It seemed to be a very casual comment. In reality, even these moons were very difficult to see. My other observing friends didn't even attempt to locate Uranus to see if they could see the moons in their C11's, C8's, and one with a large 8" ISTAR refractor.
I wonder what the smallest scopes people use to detect these two moons, and if so, what type of darkness conditions were you observing in to detect such tiny dim objects.
Are these moons about as dim and small in the eyepiece as the Planet Pluto, which is in the 14mag range?
Has anyone ever compared Pluto to these moons and if so, are the views similar?
Ive never recognized Pluto but its in a good part of the sky now for me to look for now.

...Ralph in Sacramento

Edited by aa6ww (10/08/13 07:15 PM)


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brianb11213
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Re: Nice views of Uranus and Neptune (Finally) new [Re: aa6ww]
      #6125443 - 10/08/13 05:03 PM

Quote:

I wonder what the smallest scopes people use to detect these two planets, and if so, what type of darkness conditions were you observing in to detect such tiny dim objects.



With mag. 6.2 skies (significant suburban light pollution) Uranus & Neptune are both visible with minimal optical aid, like 4x20 binoculars. (Colourless starlike points, obviously!) With slightly better skies Uranus should be a fairly easy naked eye object. I could probably see it from home if it was at the zenith instead of not even halfway up the sky when on the meridian.


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aa6ww
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Re: Nice views of Uranus and Neptune (Finally) new [Re: brianb11213]
      #6125689 - 10/08/13 07:14 PM

Sorry, I had a slight error in what I meant to say. I meant to say "I wonder what the smallest scope people have used to detect these two small moons, on the Planet Uranus, and also how dark are the skies used to see them both. I've corrected that error in my original question.


...Ralph

Quote:

Quote:

I wonder what the smallest scopes people use to detect these two planets, and if so, what type of darkness conditions were you observing in to detect such tiny dim objects.



With mag. 6.2 skies (significant suburban light pollution) Uranus & Neptune are both visible with minimal optical aid, like 4x20 binoculars. (Colourless starlike points, obviously!) With slightly better skies Uranus should be a fairly easy naked eye object. I could probably see it from home if it was at the zenith instead of not even halfway up the sky when on the meridian.




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Re: Nice views of Uranus and Neptune (Finally) new [Re: aa6ww]
      #6126364 - 10/09/13 05:04 AM

Quote:

I meant to say "I wonder what the smallest scope people have used to detect these two small moons, on the Planet Uranus, and also how dark are the skies used to see them both.



Sorry for the misunderstanding.

I've seen four moons of Uranus with 11" SCT. Titania & Oberon were pretty unmissable, Ariel & Umbriel difficult, Miranda invisible. Transparency is obviously important but a really dark sky isn't as the planet itself contributes sufficient glare to affect dark adaptation. The best power to use is probably around 20x per inch of aperture - enough to dilute the sky brightness but not enough to bloat starlike points into diffraction patterns. With larger apertures, reasonably steady seeing is also required.

As to "how much aperture is necessary" - to quote from T W Webb, "Celestial Objects for Common Telescopes":

"Ward has glimpsed the two outer moons, Oberon and Titania, with a 4.3" Wray achr, as Huggins has with 8" achr, and Sadler with a 6.5" mirror. My less acute eye has caught one with 9.3" speculum. Marth has found their visibility not affected by moonlight."

The 19th century observers were of course blessed with skies which were generally much darker than those we have today but this would be offset to a considerable extent by the extra transmission of modern scopes (multicoated lenses and more efficient mirrors: speculum metal mirrors would be only about 50% efficient even when freshly polished!)

Similarly regarding Neptune's moon Triton:

"... held by Dawes with 8" achr, no common telescope of course would touch: though Ward has glimpsed it with a 4.3" achr".

Pluto is of course omitted from the text (discovery over 70 years after the publication of the first edition). It's harder to find than Uranus's moons but probably easier to see as there's (usually) no distracting bright object in the field. This assumes similar observing conditions, but the issue with Pluto for those of us in the northern hemisphere is that Pluto is lurking fairly deep in the southern hemisphere (and will remain there for several decades) so atmospheric absorbtion and poor seeing interfere significantly.


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Re: Nice views of Uranus and Neptune (Finally) new [Re: brianb11213]
      #6126766 - 10/09/13 11:03 AM

Inspired by this thread, I found Uranus tonight for the first time this season. At around 130x in my 7in. scope, in an area of sky with a ton of light pollution (virtually no stars at all visible to the naked eye) it looked like a pale bluish little disk. No moons were visible at that mag as far as I could tell, I believe a nearby object north of it was a star. I tried to jump it up to around 250x, but the seeing and also the horrible light pollution level just couldn't support the view, I couldn'd find the planete again and that was that. But it was exhilarating while it lasted.

It is said that light pollution doesnt matter for looking at the moon, Jupiter, Mars, the bright objects... but would I be right to say that for the dimmer planets it most definitely does affect the view?


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Re: Nice views of Uranus and Neptune (Finally) new [Re: mark8888]
      #6126802 - 10/09/13 11:27 AM

Quote:

It is said that light pollution doesnt matter for looking at the moon, Jupiter, Mars, the bright objects... but would I be right to say that for the dimmer planets it most definitely does affect the view?



I would say that having Uranus in the field of view of my 11" SCT reduces the magnitude limit I am able to reach by around 1.5 ... similar to the moon a couple of days either side of full, for a "dark field" object. Really severe light pollution is of course going to have an effect. But then so does slightly inaccurate focus, poor seeing, ... and most of all the observer's experience in viewing objects close to the visual limit. A couple of years experience observing variable stars improved my threshold by around 1.5 magnitudes.


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Re: Nice views of Uranus and Neptune (Finally) new [Re: brianb11213]
      #6127435 - 10/09/13 04:58 PM

Pete, nice post and sketches--and a very nice catch of Triton in an 8-inch. I've seen it in 10 inches, but never tried 8--I'm kind of lazy that way .

-geo


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Re: Nice views of Uranus and Neptune (Finally) new [Re: aa6ww]
      #6128657 - 10/10/13 09:45 AM

Ralph,

A good read of your observations of the moons Oberon and Titania with the C-14.

Had my first chance to look for these moon with a RC20 f/8.1 on October 2, 2013 at 11:15 EDT. Low humidity and dark sky conditions.

With a 12mm (342x) the moon were just visible, very evident with the increase of magnification to 424x and then 857x.

Uranus showed a pale white center with greenish outer rim around the edges. Not expecting to see any surface on that distant planet.

The moons were at 2 and 8 position with respect of the planet Uranus. Identified them later with software Guide V8. Four of my friends were observing that night with their scopes had a chance to see these moons. Titania proved a be the more difficult to see for them. Both of the moons were around 28 arc seconds from the center of the planet on opposite sides according to the software Guide 8.

About 20 minutes later we viewed Neptune at the same magnifications and found Triton a much easier target 15 arc seconds in the 9 o'clock position from Neptune. It's position also verified later with Guide 8.

A thin veil of clouds prevented see these moons again on October 8, 2013.
Will try to show these to some of the college students taking the astronomy course at the next chance. They usually get to view these planets at low magnification.

John D Sabia


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yesplease
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Re: Nice views of Uranus and Neptune (Finally) new [Re: aa6ww]
      #6129303 - 10/10/13 03:08 PM

I'm almost positive I saw Titania Mag(13.5) on Friday and last night with my 5 inch apo. The conditions were perfect, though. I'm going to keep looking and see if I cant see it on the other side again. Both Oberon and Titania should be on the other side on the 11-12 of oct. Last night Jupiter was crystal clear at 317x, just to give an idea of how good the conditions were here.

Good info
http://www.universetoday.com/105064/uranus-a-guide-to-its-2013-opposition/


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Re: Nice views of Uranus and Neptune (Finally) new [Re: yesplease]
      #6130297 - 10/11/13 01:17 AM

Pete,
I think your color rendition of Neptune and Uranus is very much what I see. I don't have the experience of some in this thread with these planets, I usually observe them close to opposition and that's about it. But, I have been observing them since the mid 70's with 10" aperture and your drawings are captivatingly close to what I see.

Concerning color perception, I'm curious what you, or David Grey think of this online color test. I found it to be quite challenging, and after taking it I have a better idea of which colors are easier for me to distinguish subtle differences between and which are more difficult. Are tests like this informative, or bogus do you think?


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Re: Nice views of Uranus and Neptune (Finally) new [Re: Astrodj]
      #6130477 - 10/11/13 07:19 AM

"David Grey" - Who He

Scored 17/99 (0 perfect): perhaps work on your greys

Have to wonder about monitor fidelity tho' and Internet similarly.

Regards,
David (Gray).


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Re: Nice views of Uranus and Neptune (Finally) new [Re: David Gray]
      #6130684 - 10/11/13 10:00 AM

The test - lol - it annoyed me and I never completed it. All these nauseating shades of yuck. When I did try it again it was on my iphone and it didn't respond to my touch screen so I left it there.

Dave GrAy makes a good point (I too used the E come to think of it) - my iPhone is different than my laptop or pad - infact all three are slightly different. I think the absolute worst color shifts was back in the days of the fat bulky CRT screens - there was a whole host of issues there and when the even started to smell old age the colors and contrast bellied up. A new one wasn't bad but they varied still and again died early.

I'm glad you like the renderings I did - I know if I observed from a dark site that Neptune would have more teal though Im uncertain if Uranus would have changed. I would like to once and for all get 9/10 seeing or better with these two but with winter on its way the jetstream is starting to sag back down over here and that makes these two particularly vulnerable to its softening effects. Well last year at least I had 7/10 right up to the last week of November so I could luck out but it gets slim as the weeks pass.

Glad you liked my work.

Pete


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Astrodj
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Re: Nice views of Uranus and Neptune (Finally) new [Re: David Gray]
      #6131236 - 10/11/13 02:15 PM

Quote:

"David Grey" - Who He

Scored 17/99 (0 perfect): perhaps work on your greys

Have to wonder about monitor fidelity tho' and Internet similarly.

Regards,
David (Gray).




David Gray,

Please pardon my gaff, I claim exhaustion as an excuse. I'm usually very cognizant of such matters so you got me this time.

Not bragging or anything since I too wonder about monitor/screen differences, but I had a perfect score on the test (one of the reasons I wondered!). It did try my patience though. I had the most difficulty with subtle shades of the magenta/heliotrope color. I was surprised when I scored perfect as I was pretty certain I had botched some of those.

Thanks for weighing in, I value your input greatly on observing subtle planetary detail and have learned a lot from your many posts in the past.


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Astrodj
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Re: Nice views of Uranus and Neptune (Finally) new [Re: azure1961p]
      #6131292 - 10/11/13 02:42 PM

Pete,

LOL, I almost quit the test a couple of times myself as it seemed monotonous.

I have always been able to "see" very well, but I have zero talent when it comes to drawing or sketching so I admire the talented drawings I see on this forum and yours are always great. I really do appreciate what you and others achieve with various media. It is the next best thing to being able to do it myself.

I need to observe Uranus and Neptune more often. I had a very good night with Neptune last year at opposition. I was testing out a new EQ platform with magnifications of up to 600x. Once I fine tuned it a bit I settled in and observed it for a few hours at 300x and below as that was where the seeing dictated I should be. I thoroughly enjoyed myself that night. I did not discern any detail or limb darkening, nor did I glimpse anything I thought might be Triton, so I still have goals to achieve. I distinctly recall it's coloration as grey (spelling intended ), with a dark, pastel blue undertone. I can still see it clearly in my minds eye. Your drawing catches the color I saw perfectly (red zone/10" dob).


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David Gray
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Re: Nice views of Uranus and Neptune (Finally) new [Re: Astrodj]
      #6131340 - 10/11/13 03:03 PM

Thanks Asrodj,

Yes Pete saw your ‘E-type’ and let it go then it seemed to escalate after that…………..!! It rates a close second on my irritation-scale to being called a stargazer – sorry ! Perhaps we should have thought more when we called our sons Stuart & Alan (double-whammy) – and Alan in naming his, now 6 yr. old, son Korey Ayeden……… (several whammies)!

The Test: did it again and tried to put myself in observing-mode and got 3. Then I booted up my (old) workhorse PC – the one finely calibrated for my colour work. Also in a darkened room (mood-light on and some Mozart); and again in observing-mode got it down to zero first try. The newer PC has dumbed-down display setting facilities and I like it not.

The test I feel has limited application at the eyepiece: can’t slide the hues against each other there! But more in common with how I tweak colour-adjustable vectors against each other for relative hues/contrasts etc. – in connection with tinting my drawings.

At first I really could not get enthused trying this test; but now I find it a little therapeutic/compelling! Perhaps it should have a time limit option.

Doing family tree research yrs. back WWI records showed 1023 Grays killed and less than 60 Greys – not sure what that is telling me……………!

Even the spell-checker is taking issue with the ”a” – BAH!

Pardon the digressions.

All good wishes,
David.


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Re: Nice views of Uranus and Neptune (Finally) new [Re: Astrodj]
      #6131634 - 10/11/13 05:37 PM

Yes the red zone (I'm in orangey-red) does mute the colors I find. It doesn't seem like that ought to be the case but there is no doubt whatsoever in my mind that I see more color in yellow and certainly green zones. The light pollution tends to mute the finer hues . I don't see this happening in other Jupiter, Mars or Saturn but clearly with the two outter gas giants.

Glad you got the 100% on the test. Next time in at a mouse ill finally go all the way with it - disgust and all.

Also glad-

You had a terrific time with your platform. I made one myself. Once I get the drive rods machined it'll go for a spin. Even if I goofed the radi or something and I ended up with a twenty minute track time - I'd be ESTATIC. I like a lot of medium to high power work when conditions permit and it'd be such a relief to finally not need to nudge. Of my three scopes only my C6 is driven. The 70mm can eek by as mags are usually low anyway but the 8" needs a drive already.

I'm pleased you found satusfaction here!


Pete


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azure1961p
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Re: Nice views of Uranus and Neptune (Finally) new [Re: azure1961p]
      #6149218 - 10/21/13 01:38 AM

I saw Uranus for the first time using my C6. Seeing was 6-7/10 and transparency was moderate with intermittent slight haze. Best view was at 320x . I think for both my 8" and the C6 - you really want to be in the 300's to get a fair sense of surface area through scale. Color surprisingly was made out - a certain grey grey blue. It looked identical to the 8" views Ive had in the past though slightly dimmer as though a light neutral density filter was in use. Very pleasing view. Clearly non stellar at 61x. High power view was definately akin to a super high surface brightness planetary nebula. However the planet was bright enough in the 6" at this high magnification to show glare off the planets limb.

Very pleasing. Nice to track with the Celestron after nudging so much with my dob in the past.

Pete

Edited by azure1961p (10/21/13 01:44 AM)


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Re: Nice views of Uranus and Neptune (Finally) new [Re: azure1961p]
      #6149308 - 10/21/13 05:58 AM

Man, I was gonna look for Uranus last night, Pete, but the moon made star hopping pretty tough. I usually start with the circlet in Pisces and work back. That was very tough since NELM was about 4. Good on ya for doing it.

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Re: Nice views of Uranus and Neptune (Finally) new [Re: Asbytec]
      #6149707 - 10/21/13 11:44 AM

Aw, after trying to locate Neptune unsuccessfully with the Moon out last night, I gave up also on Uranus, given the time I spent trying to find Neptune. (I went to Jupiter a little later.)

I have found that for Neptune and Uranus, on nights when the Moon is more than a crescent, forget about it!


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Re: Nice views of Uranus and Neptune (Finally) new [Re: E_Look]
      #6149794 - 10/21/13 12:24 PM

Star hopping is what I do with the 8" and it can make things dicey. If there's haze the 8x50 finder with a full moon can truly be patience wearing. I've given UO more than once due to that kind of interference.

Its interesting though guys between these two scopes 300x and above is the optimum magnification . That said I believe even a 4.5" Tak apo (which according to Carlino shows more contrast than the C6) is not going to produce as good an image as the Celestron . These outter gas giants put conditions on observing that leaves small aperture high performance apo in the lurch - comparatively . In truth I can't say with certainty- I haven't done an A- B comparo with an apo on these . Still it'd seem 6" aperture is really a minimum where enough scale and brightness is comfortably achievable without feeling starved out.

Ed - I'm looking forward to your finally getting tremendous Neptune views again!!

Pete

Edited by azure1961p (10/21/13 12:29 PM)


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Ant78
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Re: Nice views of Uranus and Neptune (Finally) new [Re: azure1961p]
      #6149924 - 10/21/13 01:52 PM

I observed Uranus for the first time last night through my small scope, yellowish green with a slight limb shading.
My original plan was to locate Neptune but after a while I gave up and looked for Uranus, used Diphda as a guide star and worked north from there, the Ram constellation stars Hamal and Sheratan also helped point me to Uranus. Could not resolve any moons as they are beyond my scopes limiting magnitude but reading everyone's reports of its moons is great reading.


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azure1961p
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Re: Nice views of Uranus and Neptune (Finally) new [Re: Ant78]
      #6150966 - 10/22/13 01:20 AM

Another nice view of first Neptune then Uranus. Uranus appeared sharper and with better limb definition owing to its greater altitude in the sky. I wasn't sure completely that I had Neptune at 61x but the queer color gave it away and 226x confirmed it was the right *star*. Both were best at around 216 x due to seeing. Uranus was a far sharper orb however and tended to just lay there with it the fuzzings Neptune had.
Some of the best views so far of these with the C6.

No moons though however Triton had a field star masquerading as Triton.

Pete

Edited by azure1961p (10/22/13 09:25 AM)


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E_Look
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Re: Nice views of Uranus and Neptune (Finally) new [Re: azure1961p]
      #6152775 - 10/23/13 12:18 AM

Quote:

... No moons though however Triton had a field star masquerading as Triton.

Pete




Yeah, LOL... bin dere dun dat!


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oleg oleg
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Re: Nice views of Uranus and Neptune (Finally) new [Re: E_Look]
      #6157508 - 10/25/13 01:46 PM

Gentlemen, please explain reasonably, why is it that photographers can not get a good picture of Uranus (and Neptune) in the visible range?    On other planets (Mars, Jupiter, Saturn), they have achieved impressive results.  This raises the question, not fiction if those belts and clouds, which observers say?

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brianb11213
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Re: Nice views of Uranus and Neptune (Finally) new [Re: oleg oleg]
      #6157538 - 10/25/13 02:13 PM

Quote:

Gentlemen, please explain reasonably, why is it that photographers can not get a good picture of Uranus (and Neptune) in the visible range?



One tenth the size of Mars / Jupiter / Saturn, and lower contrast too.


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azure1961p
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Re: Nice views of Uranus and Neptune (Finally) new [Re: brianb11213]
      #6158515 - 10/26/13 12:43 AM

The two outter gas giants ask a lot of imagers even with the instruments being better than ever before. First they are dim and as a result you can't have the same frames per second that Jupiter or Venus requires. That right there makes errors in seeing more problematic than the brighter objects in our soaker system. Next is the exceeding small apparent sizes of these two - 3.5" and 2.7" for Uranus and Neptune - makes for a very seeing sensitive object. The same seeing that might soften a good Jupiter image - but still look fine, can smear an image of either of these terribly.
Their dimness coupled with the feeble light over vast distances makes it all a very condition sensitive affair.

Still these guys produce some very fine work.

Pete


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oleg oleg
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Re: Nice views of Uranus and Neptune (Finally) new [Re: azure1961p]
      #6158589 - 10/26/13 02:53 AM

There have been similar problems early 20th century, when photographers could not compete with the visual observations. With bright and large planets Mars, Jupiter, Saturn CCD techniques the problem to solved, but Uranus and Neptune are outside of the method?   They are too small and too dim, I understand you correctly?      However, 0.6-1 meter telescopes also give a fairly weak results in photographing Uranus. Their luminosity and the area is also not enough to satiate the photocell light?

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Re: Nice views of Uranus and Neptune (Finally) new [Re: oleg oleg]
      #6158763 - 10/26/13 08:53 AM

Again its a very small surface area for the size of the detector used and its often swamped by the seeing conditions that normally aren't all that bad for other scopes. Of course a 1 meter scope is going to resolve more seeing disturbance than an 8". This isn't to say the one meter isn't going to provide exquisite images - just that it is more conditional in terms if what's needed to make it happen . The scope at pic du Midi bypasses a lot if the awful *common seeing* by having a terrific site location.

I will say the best images Ive ever seen of Uranus came from Keck which resolved a chain of festoons across its equator - infra red light of course and adaptive optics.

Pete


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