The Orion Spiral Arm of the Milky Way now with added 22 image mosaic

[gregbradley]

I had some clear skies last night for a few hours so I put my new Fuji XE1 camera through its lightweight paces. This little camera packs a punch for its size. Its an APSC sized 16 megapixel sensor with its own unique colour matrix that does not require an anti aliasing filter giving it very good sharpness and it also has very good high ISO performance. Similar to my Nikon D800E.

It has a few nice features that make it easy to use at night and the zoom lens seems to be extremely high quality.

13 image mosaic of the Orion Spiral Arm of the Milky Way. ISO6400, 30 second exposures, this version was using jpegs:

http://upload.pbase.com/gregbradley/image/147759063/large regular

http://upload.pbase.com/gregbradley/image/147759063/original large

22 image mosaic:

http://upload.pbase.com/gregbradley/image/147929628/large regular size

http://upload.pbase.com/image/147929628 large size

Greg

[Paul Haese]

Nice image Greg. It shows the arm really well.

[CapturingTheNight]

Lovely image Greg :thumbsup: Love the colours you got in the stars. If I may ask: Was the halo around the brighter stars/planets due to the atmosphere at the time or post processing?

[gregbradley]

Thanks Paul. It was a lovely night and very good seeing. My imaging rig was imaging away. I saw the spiral arm quite clearly so I thought it would make a good mosaic.



Some of that is the fact it was a mosaic of 13 images. When I started around the LMC there was some high thin cloud that moved off as I went along so there is some haloing from that. I was lucky really as it was clear for a hour or so and then some partial cloud moved in later.

Greg.

[RickS]

Very nice, Greg!

[andyc]

That's lovely - can't ever recall an image where you can just 'see' an arm of the Milky Way like that. Very nicely composed.

[iceman]

Nicely done Great, looks great.

The camera certainly looks up to the task.

Why 13 images? Did you do two rows of 6 or?

[gregbradley]

Cheers Rick. Its a surprisingly good little camera.



I was imaging with my astro rig and waiting and noticed the arm so I thought it made a good imaging target.



Good question, why 13? It was primarily 4 rows of 3 and I think one from the next panorama I did as it filled in a gap.
Greg.

[Lester]

Very nice view Greg, thanks. All the best.

[Larryp]

Great image, Greg!

[SkyViking]

What a nice view, it really shows the spiral arm well and the clouds in the distance put a perspective on the scene. Great job :)

[gregbradley]

Thanks Lester. I enjoy taking these panoramas and soaking up the night sky.



Thanks Larry.



It struck me looking at it that the spiral arm was quite visible at that time.

Greg.

[madbadgalaxyman]

Hi Greg,

I really enjoyed your image of this rather neglected section of the band of the Milky Way.

I used to be a night watchman of the Milky Way, and I once knew exactly which section of the apparent Milky Way corresponds to which section of the nearby spiral structure.
I do have some recent papers about the structure of the Milky Way;
but spiral structure studies of our own Galaxy have been neglected by professionals for a couple of decades ( as there was little progress, for a long time, in figuring out the exact spiral structure of our galaxy!)

I suspect that the Orion/Monoceros Milky Way, as observed from our solar system, may be some type of feature that is in between the two major spiral arms that exist both immediately in from the sun and immediately outwards from the sun.
Certainly, the surface brightness of the Milky Way here is noticeably low.

I will see if I can find some recent plots of the three-dimensional spiral structure of our galaxy, so as to be able to figure out exactly what we are seeing here in your image.

cheers, Robert

[Ross G]

A beautiful panorama Greg.

Ross.

[gregbradley]

Thanks Robert. I would be interested in the latest models of what our Milky Way Galaxy looks like.



Cheers Ross.

Greg.

[madbadgalaxyman]

Greg,
Another obvious thing seems to be the lack of high-contrast dark nebulae in this section of the Milky Way.....or at least this seems to be the case when the band of the Milky Way here is shown at the level of contrast shown in your displayed image.

One fact of astrophysics can be expressed in the following homely way:
" No dark nebulae = no star formation"

The dust in dark nebs is mainly a tracer for the real material that is there.....the dense & cold Molecular Hydrogen Gas from which all stars are thought to form.

In fact, the actual (numerical) quantity of extinction in a dark nebula is a very good indicator of how much gas there is in the nebula!

From this observation and inference, one can conclude that the arm or inter-arm feature near Orion may well be quiescent (not forming a lot of stars, at present)

cheers, Robert

P.S. I am mainly referring to the section of the Milky Way band near Taurus and Monoceros and Gemini & Canis Major. There are some dark nebs here, but they are not as prominent as those in the Sagittarius-Carina Milky Way.

( I am not referring to the Orion star-forming complex itself.)

All in all, the section of Milky Way in your image looks very very different from the Aquila to Carina section of the Milky Way.

[naskies]

Very nice, Greg! The clouds being lit up by the nearby city lights is a nice touch.

[gregbradley]

Thanks Robert for the info.



Thanks for that. Those nearby lights are about 100kms away at least!

Greg.

[dannat]

Greg what focal length di you shoot at?

The Fuji 18-55 zoom is f2.8-4 correct? I m thinking of one for next yr, rumors of n xe2 will bring prices down

[gregbradley]

This was at 18mm F2.8.

I have heard those rumours. Its hard to believe as XE1 is a recent release - its not an old camera. I am not sure how old XE1 is but I think its only a few months.

XPro 1 has been out for a year or so and also not a particularly old camera. I'd say Fuji is more likely to update the X100 with the X-trans sensor for an X200. That makes more sense.

Greg.

[gregbradley]

I've added another mosaic I did the same night of the same Orion Spiral Arm. This one is a 22 image mosaic (3up and 7 across plus 1 near the zenith).

http://upload.pbase.com/gregbradley/image/147929628/large regular size

http://upload.pbase.com/image/147929628 large size

I think I'll do this one again next time with my D800E and compare them.

Greg.