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Barred spiral galaxy NGC 2903.

RobH

By RobH
in Imaging - Deep Sky

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RobH

RobH

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NGC 2903 is a barred spiral galaxy about 30 million light-years away in Leo just to the right of Epsilon Leonis.

It was discovered by William Herschel on November 16, 1784

It’s one of the brightest galaxies visible from the northern hemisphere but wasn’t included in Messiers’ catalogue for some reason

At 80,000 light-years across, it’s a little smaller than the Milky Way and has a very high rate of star formation near its core in visible light. A lot of the very bright starlike objects in the central region are actually very young hot globular clusters.

Imaged with a TMB 152 @F8. April & May 2011

Cameras. Atik 16HR & SXVF H18

16HR. Luminance-30 X 600s binned 1x1, Red-19 x 180s, Green-23 x 150s, Blue-21 x 240s. All colour binned 2x2.

H18. (Outer starfield only) Red-7 x 600s, Green-6 x 600s, Blue-6 x 600s.

Total imaging time-8 hrs 19 minutes.

I also shot 80 minutes of Ha, but didn’t use it as it added nothing, and a night of 10 minutes subs with my Edge 11, which turned out to be unusable due to icing on the chip, which was impossible to remove the effects of with flats.

Hope you like it.

Cheers

Rob

post-14403-133877622064_thumb.jpg

post-14403-133877622071_thumb.jpg

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Andrewsean1985

Andrewsean1985

Posted
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NGC 2903 is a barred spiral galaxy about 30 million light-years away in Leo just to the right of Epsilon Leonis.

It was discovered by William Herschel on November 16, 1784

It’s one of the brightest galaxies visible from the northern hemisphere but wasn’t included in Messiers’ catalogue for some reason

At 80,000 light-years across, it’s a little smaller than the Milky Way and has a very high rate of star formation near its core in visible light. A lot of the very bright starlike objects in the central region are actually very young hot globular clusters.

Imaged with a TMB 152 @F8. April & May 2011

Cameras. Atik 16HR & SXVF H18

16HR. Luminance-30 X 600s binned 1x1, Red-19 x 180s, Green-23 x 150s, Blue-21 x 240s. All colour binned 2x2.

H18. (Outer starfield only) Red-7 x 600s, Green-6 x 600s, Blue-6 x 600s.

Total imaging time-8 hrs 19 minutes.

I also shot 80 minutes of Ha, but didn’t use it as it added nothing, and a night of 10 minutes subs with my Edge 11, which turned out to be unusable due to icing on the chip, which was impossible to remove the effects of with flats.

Hope you like it.

Cheers

Rob

What a beautiful image! Well done :-)

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MikeD

MikeD

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Nice catch Rob on a tough target.;)

Surprised the Ha was of no use though, this target is quite rich in ha regions, although you seem to have caught most of them pretty well without dedicated ha data.

Mike.

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RobH

RobH

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Thankyou all ;)

Nadeem....I agree about the background in the wider shot....I'll lighten it up a little I think.

Kevin.....no, you can't have a shot without the spikes....I like them :D

Mike....the Ha was very noisy, and I didn't have enough to add anything useful to the image....very little effect when I pocessed it apart from a slight lightening of the core, which tended to obscure some of the fine detail so I decided against using it.

Here's the wider view with the blackpoint set at 15/15/15.....it was all at 10 before.

Cheers

Rob

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johnh

johnh

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A very good result and I prefer the lighter background, suprised you binned the colour although colour binning only has a minor effect on reducing sharpness is it the 152mm diameter not as sensitive with fainter galaxies. Suprised the Ha was poor as I would have thought this galaxy has lots. Ice on chip sounds terrible with sealed chamber it should not really happen?

Core is nicely processed as it is quite lumpy and star colour excellent as usual. Love the scope sensor combo to get the best results.

John.

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RobH

RobH

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suprised you binned the colour

John.

HJello John....binning the colour is not something I normally do, but I was under a severe time constraint, as leaving for work was looming, plus, I had to strip out the obs ready for demolition (Mk 2 will be built this summer ;)) before I went away, hence binned colour on this, and my next target to be processed, NGC 4449.

I too was surprised re. the Ha, as it's very active, so at a later stage I may well grab a lot more and reprocess.

Cheers

Rob

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ollypenrice

ollypenrice

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I was surprised to see the colour had been binned because the small scale colour detail and contrast really are impressive. You are distinguishing all sorts of tiny features here, ones rarely seen. This is a hard target pulled off to perfection. (Well, maybe I'm with Kevin on the spikes, though...)

Tremendous image.

Olly

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RobH

RobH

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Thanks again folks ;)

As for diffraction spikes....they are a matter of personal choice if you've got a refractor, and I find thay add a bit of sparkle to an image if used on selective stars. One could of course cover the entire image with them and thus stand a chance of getting an APOD :)

I treat images as bits of space art....I'm not trying to be a scientist, and if I think that something added to an unimportant part of the image makesw the whole thing more dramatic, I'll do it :D

Cheers

Rob

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RobH

RobH

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I'd love to post more Guy, but having a job that takes ma away from home for 6 months of the year, combined with the scarcity of clear skies when I am at home means that I don't actually get time to capture much data....one day, when I retire ;):D:D:D

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