The gas giant Neptune and a very, very frigid Triton.
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).
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!
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.
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.
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.
Cheers
Dennis
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.
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!
