Jump to content

  •  

CNers have asked about a donation box for Cloudy Nights over the years, so here you go. Donation is not required by any means, so please enjoy your stay.

Photo

The Rings of Uranus

  • Please log in to reply
16 replies to this topic

#1 ags55

ags55

    Vostok 1

  • -----
  • topic starter
  • Posts: 184
  • Joined: 22 Jun 2015
  • Loc: Rubyvale, Qld, Australia

Posted 18 December 2016 - 10:28 PM

http://www.acquerra....ro/uranus-ring/

 

I wish to personally thank Anthony Wesley for his advice and encouragement which made this possible, for processing the data, creating and hosting the information on his web site. It seems his part in this joint effort was much greater than mine. I hope this may encourage you all to attain what was thought impossible just a few short years ago.

Regards & Best wishes Phil.


  • Sunspot, h2ologg, John Boudreau and 7 others like this

#2 Tarzanrock

Tarzanrock

    Skylab

  • *****
  • Posts: 4026
  • Joined: 07 Dec 2008
  • Loc: Los Angeles

Posted 19 December 2016 - 01:55 AM

Impressive achievement!  Congratulations!  Thank you for posting this information and the accompanying article.



#3 stanislas-jean

stanislas-jean

    Gemini

  • -----
  • Posts: 3013
  • Joined: 22 Oct 2008

Posted 19 December 2016 - 03:37 AM

Very well done!
Stanislas-Jean

#4 PiotrM

PiotrM

    Soyuz

  • *****
  • Posts: 3842
  • Joined: 03 Jan 2010
  • Loc: Poland

Posted 19 December 2016 - 12:20 PM

I wonder what this: http://beloptik.de/d...ry-moon-viewer/ would allow to get ;) Potential is amazing.
  • Lacaille likes this

#5 ags55

ags55

    Vostok 1

  • -----
  • topic starter
  • Posts: 184
  • Joined: 22 Jun 2015
  • Loc: Rubyvale, Qld, Australia

Posted 19 December 2016 - 01:33 PM

Thank you all for your kind comments & encouragement, I have been waiting for this for a while http://bel

optik.de/de/left/planetary-coronagraph-planetary-moon-viewer/



#6 Guest_djhanson_*

Guest_djhanson_*
  • -----

Posted 19 December 2016 - 10:16 PM

Very nice work!!!  Just to quote your impressive write-up:

 

"At a guess it might be possible for
  telescopes down to about 14 inch aperture to successfully detect the very outer edges of the ring using the
  generally available NIR longpass filters (610nm / 685nm / 700nm)."

 

Damian Peach just displayed some reprocessed images of Uranus on his FB page which show the ring feature...C14!  (iR 610/224MC/40-60K)  So I think you may be right!  He stated he had very good seeing conditions. 

 

Darryl et al, it would be cool to see if you or anyone else has some long duration iR captures from this season (mine all got destroyed from my botched laptop recovery :D  woo-hoo I need to stay away from IT activities :D)

 

cheers, DJ



#7 Kokatha man

Kokatha man

    Voyager 1

  • *****
  • Posts: 12461
  • Joined: 13 Sep 2009
  • Loc: "cooker-ta man" downunda...

Posted 20 December 2016 - 03:37 AM

Phil & Anthony should be congratulated for this effort :waytogo: ...I might be the only one posting a note of caution (elsewhere) because I'd really like to see the images before they are orientated to match the Uranus Viewer orientation, making an easy & simple animation of this shift in orientation - this in the absence of sequential captures using camera re-orientation being one method to help clarify the ansae by their shift...similar in some ways to reinforcing storm data imagery via animated sequences for these Ice Giants...

 

DJ - I don't have much doubt that these types of images are evincible with a C14 in good seeing & transparency - in fact I posited this approach (iR) to Almir Germano a couple of months back...not having a CH4 filter but having one of those iR850nm filters nearer to the CH4 band's, I tried last month on a night of poor-ish seeing...it was extremely difficult to focus even without the seeing issues but I was impressed with the results, despite the seeing & 6 minutes at 2.5fps! :shocked:   :lol:

 

This filter was probably OTT wrt extreme light-diminishment & I will have a look through some of my older data when I have the time (Xmas week isn't that time! ;) ) but picking out the ring ansae is quite different imo to picking up good cloud/surface features...disk "resolution" requires careful histogram limitation as well as brightness normalization selection in AS!2 & Phil & Anthony indicated they had fairly high gain/histogram settings for their captures here...but I do have some files that might fit the bill however. ;)

 

I should also note however that this iR850nm image was taken at over 8000mm f/l with the ASI290MM...native f/l, a good night & many more than 531 frames - who knows..?!?

 

Oliver's device looks like it could be a real boon for us Outer Planet imagers but my last take was that he was off cycling for a year - I don't know exactly how much time he puts into bringing these devices onto the market...but it sure seems interesting despite the limited info I've been able to find out about it... 

 

Any new imaging sessions are really compromised for us as I said to Christian this morning...it isn't really feasible to image before 9:15pm due to the light & Uranus culminates at 8:06pm which even at Carrieton 400km North is just 50° - Phil & Anthony have Uranus at another +9° which helps keep it higher for longer once it's dark enough to image. Rings, with transparency a vital aspect along with sufficient darkness makes our possibilities very dim! (pardon the pun)  ;)

 

Just to clarify to Phil & Anthony it'd be nice to see the image of Uranus as a simple 2-frame animation of the before & after orientating to the Uranus Viewer's aspect...I, like a lot of others "think" we can see the ring ansae at "7o'clock" in the relevant image but seeing it shift with the changing orientation would (possibly) make it clearer - & extremely simple to create said "animation"..!

 

With those first AA images of Saturn's NP hex some years back we personally experienced quite a lot of incredulity & scrutiny - deservedly so imho - for something that was much more apparent...& like then & now, people then went through their older data asserting it was evincible therein: if this data is verified - & it does appear to be the case that many are convinced this evidence is incontrovertible already - Phil & Anthony's captures deserve respect for them having achieved this feat! :waytogo:  :waytogo:

 

EDIT: As an example here's that iR850 Uranus image (no sharpening of the disk) where I have re-orientated the 2nd frame to match the Uranus Viewer's simulation of this (bad! ;) ) image...Ariel was utilised (it was revealed in the capture) but I have cropped it out of this gif to avoid its' distracting appearance...similarly I have removed the Uranus Viewer simulation because, as I remarked in the Planetary Imaging forum having this "blink" in the sequence makes one believe the ring ansae outline is present when in fact it isn't...as I said, a simple thing for you fellas to make! ;)

 

Uranus_123303_ir850_231116.gif  

 

EDIT#2:  ...just to also clarify the problem using the Uranus Viewer to blink" with any Uranus image I'll post the above image with a Uranus Viewer aspect overlay, where the eye & brain can be easily tricked with this type of display - but I should point out Phil & Anthony have not used this type of animation, to their credit imho.

 

Uranus_123303_ir850_231116_BLINK-UViewer.gif


Edited by Kokatha man, 20 December 2016 - 05:34 AM.

  • Eltanin and Lacaille like this

#8 stanislas-jean

stanislas-jean

    Gemini

  • -----
  • Posts: 3013
  • Joined: 22 Oct 2008

Posted 20 December 2016 - 04:39 AM

Personnally, on paper it would be possible to acquire the anse rings with a 300mm superpolished, flocked, to reduce diffusion of light, but rather having an excellent night, low seeing level, undusty, no moisture in air. Elevated sites will be an help to reduce the local atmosphere thickness. This would improve the 500mm data by 3dB minimum.

The focal ratio of F8-10, I think would be optimum, so acquisition at the focus point with a barlow for F20.

We need minimum sizes of the objects aimed (planet 0.1mm and rings 0.2mm). A compromise. 

The occulter could be created from a L filter (having be sure it transmits NIR segment and optically acurate) where droplets of paint will be deposited (a small one needed) from black paint spray can and in order to save the high cost of  the professional occulter device suggested above .

Not easy but can be tried for rings only.

With an excellent stable mount and tracking.

A suggestion.

Stanislas-Jean



#9 Kokatha man

Kokatha man

    Voyager 1

  • *****
  • Posts: 12461
  • Joined: 13 Sep 2009
  • Loc: "cooker-ta man" downunda...

Posted 20 December 2016 - 08:22 AM

I see you've been on the forum Phil but not responded to my post: perhaps you're looking at your data to put together something along the lines of what I'm suggesting...I've made the same request to Anthony on the P.I. forum as well... ;)

In case there's some sort of misunderstanding of my position here I'll reiterate - I suspect that the periphery of the ring ansae has been evinced - more so at that 7 o'clock position as generally agreed - perhaps...

I use the phrase "the periphery of the ring ansae has been evinced" rather than Anthony's

Quote: <"Due to the proximity of the ring to Uranus and its extremely low brightness only the ends of the
ring (ansae) are detected, with the interior lost in the glare and scattered light from Uranus.">

- because to the best of my abilities in scrutinising these images of yours (particularly #3) I can only detect some vague contrast/brightness variation where I "think" these elements appear - hence my "perhaps."

My eyesight may of course be worse than I think, in which case I apologise profusely..! ;)

I have to say that measuring the distance from the nearest point on Uranus' disk edge (either the bloated disk or the presumably accurately-centred U.V. sim. overlay) to either the inner or outer aspects of the lower ansae in the 2nd image of #3 on Anthony's site (ie, the one with the Uranus Viewer simulation overlaid) only makes the whole matter more confusing for me if I apply these measurements to the image of #3 above this.....

Without any prejudice or intention of offense, none of what Anthony says in the accompanying text seems to state anything other than:

Quote:<"The ring is detected in each of these analyses. It is most clearly seen in analysis #3">

Despite the description of the various capture parameters etc & some speculative comments I'm no more enlightened...thus my request for a simple animation to reinforce your claim...

I'm sorry if I'm persistent & I appreciate that folks here can be sceptical ;) - I've had to "defend" our own Uranus images amongst other work here from time to time & may not have quietened those doubts at times myself...but it is reasonable to debate these matters imho! :)
  • sfugardi and Eltanin like this

#10 MalVeauX

MalVeauX

    Fly Me to the Moon

  • *****
  • Posts: 5219
  • Joined: 25 Feb 2016
  • Loc: Florida

Posted 20 December 2016 - 03:28 PM

This is really cool, thanks for the effort and sharing!

 

Very best,



#11 Bird

Bird

    Soyuz

  • *****
  • Posts: 3949
  • Joined: 07 Aug 2003
  • Loc: Rubyvale, Australia

Posted 20 December 2016 - 05:14 PM

Hi Darryl, just to put your mind at rest, I wanted to make sure you understood how we aligned the data...

 

See the attached two images, Phils data is presented here in the same orientation as captured by the camera, and the simulated view is just as-is out of the software. If you scale the simulated image to a width of about 230 pixels, and then rotated it 7 degrees then the moons align with those in Phils image, and then you can see that the ring is exactly where it should be.

 

Phil already had the camera rotation set to be "equatorial", ie with RA left/right and DEC up/down, but as this was set by eye it's not surprising to find a 7 degree offset.

 

To be clear, let me repeat that we used the moons as our alignment reference when doing this, not Uranus. Otherwise we would not know the correct scale or accurate orientation.

 

cheers, Bird

Attached Thumbnails

  • 2016-12-13-1136_1-PMRQA-610.png
  • 2016-12-13-U-sr.png

  • Eltanin and happylimpet like this

#12 Marc Delcroix

Marc Delcroix

    Viking 1

  • -----
  • Posts: 504
  • Joined: 26 Aug 2007
  • Loc: France

Posted 20 December 2016 - 05:46 PM

I think that animation demonstrates better at least a very fortunate coincidence of having the bottom part of the simulated ring overlap the feature on the Uranus image :

u2016-12-13-1136_1-PMi_anim.gif


  • Eltanin likes this

#13 Kokatha man

Kokatha man

    Voyager 1

  • *****
  • Posts: 12461
  • Joined: 13 Sep 2009
  • Loc: "cooker-ta man" downunda...

Posted 20 December 2016 - 07:49 PM

Hi Darryl, just to put your mind at rest, I wanted to make sure you understood how we aligned the data... 
Phil already had the camera rotation set to be "equatorial", ie with RA left/right and DEC up/down, but as this was set by eye it's not surprising to find a 7 degree offset. 
To be clear, let me repeat that we used the moons as our alignment reference when doing this, not Uranus. Otherwise we would not know the correct scale or accurate orientation. 
cheers, Bird


Anthony mate! :lol: No-one with any nous has any doubts about the process of using the moons to align either PDS or WinJupos simulations with their own captures..!

I clearly explained this in my examples above but removed Ariel to stop its distracting appearance/motion... ;)

If you bother to look at any single posting of ours here on CN or elsewhere re Uranus or Neptune you will see this re-orientation legend in all the images, complete with estimated amount in degrees.

Please, perhaps it is just your measured way of thought-processing but it really does seem like 2 people speaking different languages at times...I know I can be a bit quick as well as obtuse at times, but nothing you have said above has added anything to the facts...my own suggestion would have been putting the images etc out with your own conclusions & exposing them to public rigour where awkward questions are more likely to arise imo...I frequently "speculate" in our own images/postings re the Ice Giants but always add some very sceptical riders to those comments. ;)

As I have just said here https://www.facebook...04436579601722/ there is nothing stopping either of you from using Phil's image "out of the can" so to speak & then re-orientating it to conform to the PDS simulation instead of vice-versa...you then have 2 orientations of Phil's image to animate & provide extra viewing appraisals (ie, as per my first image in Post #7)...of course this approach will only highlight whatever is there & not add any more proof - but nobody would be in any doubt as to what is being referred to in your image/s by creating said animation. (see additional comment re this in my response to Marc in this post further down...)
 
 

I think that animation demonstrates better at least a very fortunate coincidence of having the bottom part of the simulated ring overlap the feature on the Uranus image :


Marc, speaking of language difficulties I should first state that my French is pathetic at best, whereas your English is in comparison far superior..! :)

Notwithstanding this, it seems that you fail to appreciate the intent of the 2nd small image I have included in my first post further up (#7) nor any of my comments therein when you posted this blink animation above! :)

Your animation using Phil & Anthony's data plus the PDS simulation only serves (apart from the dangers I articulated for my own image in Post #7) to highlight the fact that that "detail" at the 7 o'clock position is markedly shifted to the right in their image - & does not conform with either the inner or outer edges of the ring ansae...

I've refrained from posting an animation I could make myself from the data because I do not consider it my prerogative to utilise their images, which is why I've asked them to do so themselves... :)

Incidentally, as I said in the Astronomy Planetary Imaging Forum there is really no comparison whatsoever with the Pic du Midi images of 24-10-02 you posted there...quite understandably! ;)

I'm sorry if I'm ruffling any feathers here because that is not my intent: as I said on the API forum "the more I look the less I see" - or perhaps better said as "the more dubious I become."

Mutual back-slapping does not constitute proof, especially when there are obvious flaws in the evidence presented...it might well be some aspects of light & optics come into play here as I believe Grant suggested in the other forum...Phil & Anthony might well have laid an important foundation stone in this search to detect the rings of Uranus with this data & I'm sure will be more rigorous in areas that patently require it the next time...such as camera re-orientation between captures...

This is nearly always the case where the investigator/s see aspects of their endeavours that require further refining to achieve their objectives...& they should be applauded regardless of whether any or all are convinced about these results...I for one am not but that should take nothing away from their efforts..! :) :waytogo:
  • exaxe likes this

#14 Quaternion

Quaternion

    Messenger

  • -----
  • Posts: 439
  • Joined: 08 Dec 2011
  • Loc: USA

Posted 21 December 2016 - 07:14 AM

Fantastic work Phil. It seems just a few years ago amateur astronomers were struggling to capture banding on the surface of Uranus, and now you've actually detected the rings on an object that subtends what 3.7asec !!!

I see it was also accomplished with Point Grey's (now FLIR) IMX250 based sensor that I've been trying to talk ZWO into building. I wonder if the global shutter played a role in this capture? Regardless, congratulations!!!

#15 Quaternion

Quaternion

    Messenger

  • -----
  • Posts: 439
  • Joined: 08 Dec 2011
  • Loc: USA

Posted 21 December 2016 - 07:19 AM

Fantastic work Phil. It seems just a few years ago amateur astronomers were struggling to capture banding on the surface of Uranus, and now you've actually detected the rings on an object that subtends what 3.7asec !!!

I see it was also accomplished with Point Grey's (now FLIR) IMX250 based sensor that I've been trying to talk ZWO into building. I wonder if the global shutter played a role in this capture? Regardless, congratulations!!!

#16 Bird

Bird

    Soyuz

  • *****
  • Posts: 3949
  • Joined: 07 Aug 2003
  • Loc: Rubyvale, Australia

Posted 21 December 2016 - 05:05 PM

If we get another night of "perfect" seeing then rotating the camera is certainly one of the things on our list to try - although of course just rotating the camera is not sufficient, you need to rotate everything in the optical system to be sure (including spider vanes, primary mirror etc) and some of those are not possible to do.

 

The only question is *when* we might get this sort of seeing again? Phil & I have checked all the Uranus data we have going back a couple of years and there are no other nights with seeing that was even remotely close to Dec 13. Interestingly, Damian has also let me know that he's done this as well, gone back through all of his Uranus data as far as 2007, and he has just the one night (Oct 31 2015) of "good enough" seeing where the ring shows up clearly in his data. I'm sure you've all seen his image of the ring from that night that he posted last week.

 

The only conclusions I can draw from this is that: (1) The ring can be detected in scopes as small as 14" (and maybe smaller) in perfect seeing, and (2) that sort of seeing is exceptionally rare.

 

Note: Damians image was captured close to opposition when the rings may have been brighter than normal due to the Uranus equivalent of the Seeliger effect... so that suggests a good time to go looking.

 

cheers, Bird


Edited by Bird, 21 December 2016 - 05:20 PM.


#17 Kokatha man

Kokatha man

    Voyager 1

  • *****
  • Posts: 12461
  • Joined: 13 Sep 2009
  • Loc: "cooker-ta man" downunda...

Posted 21 December 2016 - 10:27 PM

Apologies, been up at Sedan all night! ;)

 

Your last post really doesn't advance anything anymore than the previous one Anthony, which was quite irrelevant to my questions anyway...except I see that the "excellent" seeing is now upgraded to "perfect."  :grin:

 

As I have explained I now create image legends revealing the degree of orientation of our images, relative to any simulations.....& also include the specific focused star's Airy Disk which we used to collimate...

 

Do you have any objective evidence, rather than anecdotal, to support this seeing quality assertion..?

 

Recently I explained on this forum that although this A.D. image will not tell you everything that the actual imager would be aware of, it does provide a fairly good indication of the relative atmospheric steadiness, or seeing quality...perhaps Phil has this information available...not necessarily obtained via our "manual" approach - but perhaps using MetaGuide for example..?

 

I consider this collimation information vital for separating accurate seeing appraisals from bull-dust actually...most especially for the Ice Giants where, might I suggest, Pat & myself have considerable experience. ;)

 

Incidentally, were you present when Phil actually recorded these data sets..?

 

I'm happy to give anyone credit where it is due as I have said before; but nothing has been added to the (original) data to reinforce their clarity or confirm their veracity...despite your suggestion that aspects other than camera rotation are necessary for proof - even stranger in that you list elements that you yourself then immediately admit are impossible to rotate!!! :confused:  :rofl:

 

​I'm concerned that the same responses that fuel Facebook, Twitter & a large percentage of internet forums etc is apparent in this matter where little or no objective rigour is applied to claims on the flimsiest of evidence...& "bandwagon back-slapping" provides the imprimatur of fact.....this might well be a valid claim which I'll repeat for the 4th or 5th time now - but it is a dis-service to that possibility when nothing but frippery concerning well-known aspects of the imaging of Uranus etc are the only additional reinforcements to the argument! ;)

 

Quarternion- Sam Wen rejected the IMX250 as a ZWO camera sensor in discussions I had with him about this about a year ago...there are numerous reasons why he selected the IMX290 sensor & as for the global shutter question...if other claims of detecting the Uranian Rings are also correct then this feat has been achieved with not only rolling shutter sensors but (heaven forbid! :lol: ) with colour cameras as well..! :)




CNers have asked about a donation box for Cloudy Nights over the years, so here you go. Donation is not required by any means, so please enjoy your stay.


Recent Topics






Cloudy Nights LLC
Cloudy Nights Sponsor: Astronomics