Return to the Cloudy Nights Telescope Reviews home page


Observing >> Solar System Observing

Pages: 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | (show all)
Savio Fong
Vendor (Galaxy Scientific)


Reged: 10/05/09

Loc: Hong Kong
Re: C/2012 S1 ISON new [Re: Savio Fong]
      #6144209 - 10/18/13 03:23 AM

My best animation of C2012 S1 as of today, taken from my robotic observatory in Tibet this norming. Universal Time 2013-10-17, 21:18-22:51

~17Mb, click and wait till download finished,
http://www.astro.hk/C2012_S1_Mars_Regulus_L-120S-20131017-UT2118-2251.gif

stack of 25x120s as follows,
http://www.astrocafe.hk/download/file.php?id=9269


Post Extras: Print Post   Remind Me!   Notify Moderator  
BrooksObs
professor emeritus


Reged: 12/08/12

Re: C/2012 S1 ISON new [Re: CygnuS]
      #6144396 - 10/18/13 08:37 AM

Quote:

Hey, I just had a thought. If ISON breaks up and never even gets bright enough to be seen in 8 inch scopes will my special edition of Astronomy magazine become a collectors item just like the newspapers that printed Dewey winning the US presidency? I suspect that 90% of them will be thrown out in disgust and the survivors will be rare as oddities.
I'm not exactly going to plan my retirement on the value of this potential collectors item. Besides, I'm still rooting for the comet to live up to the hype started nearly a year ago. Increasingly it doesn't look like that's going to happen.




Not very likely. There is a wealth of Comet Kohoutek material always to be found on eBay that sells for minimal price. Thus, I wouldn't anticipate any different situation with Comet ISON. Likely the best place to ultimately store your copy of Astronomy Magazine's special Comet ISON issue will be in the well know "circular file" for weekly disposal!

BrooksObs


Post Extras: Print Post   Remind Me!   Notify Moderator  
BrooksObs
professor emeritus


Reged: 12/08/12

Re: C/2012 S1 ISON new [Re: BrooksObs]
      #6144477 - 10/18/13 09:23 AM

While I would be the first to admit that the many images, particularly the color ones, we are seeing posted on the Internet are impressive, for the most part they do not convey two rather obvious potential problems with C/ISON.

On images C/ISON looks big and health, but what is mostly missing from the images is a scale indicating image size. The nice, bright, seeming "head" of C/ISON on images is little more than a mere 1' in size. For a comet currently just 1.3AU from the Sun this is unusually small. Visual observers are mostly reporting a faint and diffuse outer coma up to 4' in size, but this is very weak.

At the same time, most any significant comet will show indications of streamers in the tail by the time it has closed to within 1.3 AU. C/ISON's tail exhibits absolutely no streamer features, generally indicative of very low outgasing.

Both of these situation tend to be commonly seen in regard to small periodic comets, not major objects. Thus, I'm concerned just what this has to say about C/ISON. I remember that at a recent C/ISON conference a prominent professional astronomer in the comet field called ISON gas starved and, "a flying dust-ball". I only hope that he may be wrong for observers' sake.

BrooksObs


Post Extras: Print Post   Remind Me!   Notify Moderator  
canukLX90
professor emeritus


Reged: 12/25/08

Loc: B.C. Canada
Re: C/2012 S1 ISON new [Re: BrooksObs]
      #6144949 - 10/18/13 01:52 PM

Your image scale comment noted. I will include scale info
on future image posts along with the equipment and
processing steps.

PJ


Post Extras: Print Post   Remind Me!   Notify Moderator  
CygnuS
sage


Reged: 07/11/11

Loc: The Great Rift
Re: C/2012 S1 ISON new [Re: BrooksObs]
      #6145239 - 10/18/13 04:54 PM



Not very likely. There is a wealth of Comet Kohoutek material always to be found on eBay that sells for minimal price. Thus, I wouldn't anticipate any different situation with Comet ISON. Likely the best place to ultimately store your copy of Astronomy Magazine's special Comet ISON issue will be in the well know "circular file" for weekly disposal!

BrooksObs



I hope everybody listens to your wise advice and throws theirs away. That way I'll have the only one left and I WILL be able to retire when selling it. Seriously though, I'm just going to add it to my collection and laugh at it in 20 years then die and make my kids throw it out.


Post Extras: Print Post   Remind Me!   Notify Moderator  
Mike B.
Carpal Tunnel
*****

Reged: 10/24/05

Loc: Louisiana
Re: C/2012 S1 ISON new [Re: BrooksObs]
      #6145561 - 10/18/13 08:33 PM

Quote:


On images C/ISON looks big and health, but what is mostly missing from the images is a scale indicating image size. The nice, bright, seeming "head" of C/ISON on images is little more than a mere 1' in size. For a comet currently just 1.3AU from the Sun this is unusually small. Visual observers are mostly reporting a faint and diffuse outer coma up to 4' in size, but this is very weak.




Yes, I agree. Gauging the size is hard for a little comet like ISON. Here's what I usually do for my comet images:



I looked up the distance between two stars in the image with Cartes du Ceil and created the scale bar based on that. So, it might be off +/- 20 seconds.


Post Extras: Print Post   Remind Me!   Notify Moderator  
Tonk
Postmaster
*****

Reged: 08/19/04

Loc: Leeds, UK, 54N
Re: C/2012 S1 ISON new [Re: Mike B.]
      #6146072 - 10/19/13 05:10 AM

Mike - you could also post the image to AstroBin (free) or any other online astrometric service and the image is plate solved and dimensions returned to you (or appended to the gallery notes for the image when building your gallery on AstroBin - example here http://www.astrobin.com/33885/ )

Post Extras: Print Post   Remind Me!   Notify Moderator  
Mike B.
Carpal Tunnel
*****

Reged: 10/24/05

Loc: Louisiana
Re: C/2012 S1 ISON new [Re: Tonk]
      #6146995 - 10/19/13 04:28 PM

Quote:

Mike - you could also post the image to AstroBin (free) or any other online astrometric service and the image is plate solved and dimensions returned to you (or appended to the gallery notes for the image when building your gallery on AstroBin - example here http://www.astrobin.com/33885/ )




Doh! Yes, you are right. I had already posted it and plate solved it at Astrobin. I could have easily calculated the width in pixels with the data:

RA center: 10:09:51.065
DEC center: +13:57:27.029
Pixel scale: 2.24 arcsec/pixel
Orientation: -178.02 degrees
Field width: 52.31 arcminutes
Field height: 35.15 arcminutes

Live and learn, as they say. heheh

Edit: Got it: 268.4 pixels! My bar is a teeny, tiny hair shy of 268. lol

Edited by Mike B. (10/20/13 12:33 PM)


Post Extras: Print Post   Remind Me!   Notify Moderator  
BSJ
Pooh-Bah
*****

Reged: 12/22/08

Loc: Grand Isle, VT
Re: C/2012 S1 ISON new [Re: Mike B.]
      #6149356 - 10/21/13 07:36 AM

"This disintegration will take place before it reaches perihelion,"

http://www.spacedaily.com/reports/Is_the_Christmas_Comet_cracking_up_999.html


Post Extras: Print Post   Remind Me!   Notify Moderator  
BrooksObs
professor emeritus


Reged: 12/08/12

Re: C/2012 S1 ISON new [Re: BSJ]
      #6149507 - 10/21/13 09:36 AM

Quote:

"This disintegration will take place before it reaches perihelion,"

http://www.spacedaily.com/reports/Is_the_Christmas_Comet_cracking_up_999.html




Sadly, just a rehash of misinformation put forth by "staff writers" and one supposed South American "astronomer" with a highly questionable reputation for making predictions that don't pan out.

BrooksObs


Post Extras: Print Post   Remind Me!   Notify Moderator  
TxStars
Pooh-Bah
*****

Reged: 10/01/05

Loc: Lost In Space
Re: C/2012 S1 ISON new [Re: BrooksObs]
      #6149658 - 10/21/13 11:11 AM

Perhaps we could still win the comet loto and get a fantastic naked eye view.

Post Extras: Print Post   Remind Me!   Notify Moderator  
Rocky68d
member


Reged: 11/01/09

Loc: Anacortes, WA USA
Re: C/2012 S1 ISON new [Re: TxStars]
      #6150080 - 10/21/13 03:37 PM

This is indeed a rehash. I found an article from February of this year with these same quotes from Ferrin.

Post Extras: Print Post   Remind Me!   Notify Moderator  
Scanning4Comets
Markus
*****

Reged: 12/26/04

Loc: Ontario, Canada
Re: C/2012 S1 ISON new [Re: Rocky68d]
      #6154810 - 10/24/13 04:27 AM

Great pic Mike!

Post Extras: Print Post   Remind Me!   Notify Moderator  
Mike B.
Carpal Tunnel
*****

Reged: 10/24/05

Loc: Louisiana
Re: C/2012 S1 ISON new [Re: Scanning4Comets]
      #6158125 - 10/25/13 08:11 PM

Quote:

Great pic Mike!




Thanks, Markus!

Here's one I think everyone will appreciate - a comparison of Comet ISON taken this morning (Oct 25th, 2013) and the image I took 10 days ago on Oct 15th:



I used the exact same equipment and image crop pixel dimensions, so it is a pretty good comparison. What do y'all think? Doubled in size or so?

I was pretty impressed at how much it has grown in the short time since I last devoted a morning to it. Even with a bright moon nearby, it still had considerable signal and it did not get washed-out by moonlight like I thought it might.

Edit: A link to the "final" Oct 25th version is here.

Edited by Mike B. (10/26/13 09:20 AM)


Post Extras: Print Post   Remind Me!   Notify Moderator  
CygnuS
sage


Reged: 07/11/11

Loc: The Great Rift
Re: C/2012 S1 ISON new [Re: Mike B.]
      #6158383 - 10/25/13 10:54 PM

Fantastic Mike!
Thanks so much for sharing these. Great work!


Post Extras: Print Post   Remind Me!   Notify Moderator  
Rich (RLTYS)Moderator
Postmaster
*****

Reged: 12/18/04

Loc: New York (Long Island)
Re: C/2012 S1 ISON new [Re: Mike B.]
      #6158687 - 10/26/13 07:00 AM

Has anyone noticed the ISON's tail has a reddish hue?

Rich (RLTYS)


Post Extras: Print Post   Remind Me!   Notify Moderator  
BrooksObs
professor emeritus


Reged: 12/08/12

Re: C/2012 S1 ISON new [Re: Rich (RLTYS)]
      #6158782 - 10/26/13 09:14 AM

Quote:

Has anyone noticed the ISON's tail has a reddish hue?

Rich (RLTYS)




Of course. It's a dust tail.

BrooksObs


Post Extras: Print Post   Remind Me!   Notify Moderator  
Tonk
Postmaster
*****

Reged: 08/19/04

Loc: Leeds, UK, 54N
Re: C/2012 S1 ISON new [Re: BrooksObs]
      #6158918 - 10/26/13 10:48 AM

Quote:

Of course. It's a dust tail.




Indeed - Comet Garradd (from a couple years back) also had a noticeable orange-red tint to its tail


Post Extras: Print Post   Remind Me!   Notify Moderator  
canukLX90
professor emeritus


Reged: 12/25/08

Loc: B.C. Canada
Re: C/2012 S1 ISON new [Re: Mike B.]
      #6159227 - 10/26/13 01:53 PM

Thanks for posting...great images and I do like the
comparison showing how this comet is developing.

PJ


Post Extras: Print Post   Remind Me!   Notify Moderator  
urassner
sage
*****

Reged: 07/08/12

Re: C/2012 S1 ISON new [Re: canukLX90]
      #6160699 - 10/27/13 12:46 PM Attachment (52 downloads)

First attempt at Ison from the City with a DSLR (did not have a remote release, hence the artifact on the brighter star). Animated gif from 13 15 seconds exposures over 9 minutes. Taken through a TV Genesis SDF. It is amazing to me how fast it moves. Had to compress it quite a bit to get it to 200 kb.

Post Extras: Print Post   Remind Me!   Notify Moderator  
Pages: 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | (show all)


Extra information
1 registered and 3 anonymous users are browsing this forum.

Moderator:  Rich (RLTYS), star drop 

Print Thread

Forum Permissions
      You cannot start new topics
      You cannot reply to topics
      HTML is disabled
      UBBCode is enabled


Thread views: 21561

Jump to

CN Forums Home




Cloudy Nights Sponsor: Astronomics