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View Full Version here: : The gas giant Neptune and a very, very frigid Triton.


Dennis
29-07-2012, 02:42 PM
Hello,

Here is an image of the gas giant Neptune with its largest moon, Triton taken with a Celestron C9.25 from our back yard in Brisbane. I have included some screen prints from The Sky X and SkyTools 3 Pro for further information. Neptune and Triton were separated by 13.7 arc secs when the image was captured.

Imaging details:

Celestron C9.25 F10 with Tak x1.6 Extender giving an efl of 3760mm at F16.
SBIG ST2000XM CCD camera.
LRGB 10x15 secs each.
Brisbane Qld, Australia.
Saturday 28th July 2012 from 10:49-11:07pm AEST (UT+10)

Background information:
Neptune is the eighth and farthest planet from the Sun in the Solar System. It is the fourth-largest planet by diameter and is 17 times the mass of Earth. On average, Neptune orbits the Sun at a distance of 30.1 AU, approximately 30 times the Earth–Sun distance.

Triton is the largest moon of Neptune, with a diameter of 2,700 kilometres. William Lassell, a British astronomer, discovered Triton on October 10, 1846 scarcely a month after Neptune was discovered. Triton is colder than any other measured object in the Solar System with a surface temperature of -235° C (-391° F).

Cheers

Dennis

FlashDrive
29-07-2012, 02:45 PM
Well done Dennis .... great work ... especially from a back yard in Brissy .

Flash :D

multiweb
29-07-2012, 03:03 PM
Great catch Dennis and excellent read. :thumbsup:

Troy
29-07-2012, 03:31 PM
Not a bad effort Dennis :thumbsup:
The moon itself looks great but I guess the long exposure helps
This planet is on my to do list one day 8-)

kustard
29-07-2012, 03:41 PM
Nicely done :)

RickS
29-07-2012, 03:48 PM
Great capture, Dennis!

Dennis
29-07-2012, 05:36 PM
Thank you everyone for your nice words, I appreciate you having a peek and leaving a comment!:)

It turned out to be quite a hard night’s work – the seeing was very poor and at 3760 mm efl, the somewhat dim light was being smeared to such an extent that at one stage, I thought that I had slewed to the wrong object as Triton was not immediately obvious!:lol:

I was surprised at Neptune’s somewhat greenish tinge, straight out of the camera. I had the R:G:B ratio set at the default of 1:1:1 in CCDStack where I assembled the LRGB. The filters are the Astronomik RGB Type II. Just reading around a little now, makes me think that 0.65 : 0.98 : 1 might be more accurate pending a calibration run down the track.:shrug:

Cheers

Dennis

rogerg
29-07-2012, 06:05 PM
Great image Dennis, inspring and interesting :thumbsup:

RobF
29-07-2012, 07:18 PM
Nice one Dennis. Surprising we don't see Nepture in the forums more. Thank goodness for your originality!

peter_4059
29-07-2012, 07:22 PM
Great capture Dennis.

Dennis
29-07-2012, 08:54 PM
Thanks Roger, Rob & Peter.

I’ve just created a composite of the 10x15 sec RGB Neptune and a set of 10x30 sec Lum background to bring in some of the fainter stars that were only hinted at previously. I also combine the R:G:B at a ratio of 0.65:0.95:1 and I think that Neptune’s colour looks a little more “realistic”.

Hopefully you cannot see the joins – with so little data the background was awful to play around with.:)

Cheers

Dennis

Clayton
30-07-2012, 08:15 PM
Lovely job Dennis :thumbsup::thumbsup:
And the repro's are even better :)

iceman
31-07-2012, 06:07 AM
Nicely done Dennis!

DavidTrap
31-07-2012, 07:51 AM
Great work as usual Dennis.

I was wondering about the colour - reprocess looks much more like it!

DT

RB
31-07-2012, 08:21 AM
Dennis lovely work as usual, I love how you go after the more difficult objects.
I can only imagine how many obstacles you were up against and to grab Triton too, well done once again.

I too was a little surprised at the greenish tinge of Neptune, thought it was just me though.
The repro looks much more realistic and what I rememnber seeing it as.

:thumbsup:

bigjoe
31-07-2012, 12:23 PM
Simply fantastic. One day I'll get the chance to do similar Dennis
cheers bigjoe

Ric
31-07-2012, 02:23 PM
lovely work Dennis

I really enjoyed the write up.

Cheers

Max Vondel
31-07-2012, 03:22 PM
Very nice Dennis.
I believe that Uranus and Neptune are own officially called "Ice Giants"
;)

Dennis
01-08-2012, 08:46 PM
Thanks Rob, Mike, David, Andrew, Joe, Ric and Peter – I appreciate your appreciation!:)

I’ve attached a “before” and “after” image to this reply to provide compare and contrast the ‘raw” LRGB from CCDStack before it was opened in Photoshop to finish off the processing.

I’ll leave it to the informed Ice In Space readers to decide which is which!;)

Cheers

Dennis

Quark
02-08-2012, 09:46 AM
Nicely done Dennis and very well presented, as usual.

Regards
Trevor