The 'Andromeda Shelf' - real or spurious?

[ollypenrice]

In another thread http://stargazerslounge.com/topic/240497-surface-brightness-higher-better/#entry2608913 PeterW posted this very interesting link.

The third drawing down shows what the observer calls 'The Andromeda Shelf.' This was new to me and I have a farily deep M31 with about 15 hours of luminance from a dark site at F5.  However, this is Mel Bartels in action and he is an observer not to be taken lightly, so I don't take him lightly! 

None the less there are anomalies between his sketch and our image.

http://ollypenrice.smugmug.com/Other/Best-of-Les-Granges/i-3D2Hw7s/0/X3/M31%20Outer%20Halo-X3.jpg

Our image finds sufficient nebulosity to embrace both satellites yet it doesn't find any trace of the loop-like extension which I assume to be the Shelf. His sketch finds less M31 halo but does find the Shelf.

Anyone know more about this? Any widefield images out there which find it? One thing's certain, we have a summer project!

Olly

[Qualia]

I don't know anything about this, Olly but I salute your original scepticism. I mean, I'd be very suspicious that it is actually a part of M 31. If there is nebulosity, I imagine it's within the Milky Way and has been sketched as a line of sight object. 

Maybe it's worth a hunt at your sight in France with a set of binos?

[wxsatuser]

Quote

"considering that the distance to M110 and The Andromeda Galaxy that floats just above it are hundreds of times further away."

Seems the shelf is not part of Andromeda but a lot closer.

[ollypenrice]

Could be 'IFN' stuff. Has anyone found any photographs of it?

Olly

[wxsatuser]

Here you go Olly.....does this show it

http://www.astrobin.com/102376/C/

[ollypenrice]

Here you go Olly.....does this show it

http://www.astrobin.com/102376/C/

Ah yes indeed! That's great, thanks. One of Hytham's, too. He hasn't posted for a while on here. The loop feature is pretty wide.

Olly

[Uranium235]

Very interesting..... never knew it existed. But if our MW has IFN, then its proabably a common thing.... along with tidal tails etc.

I can imagine it requiring ultra-dark skies, a big FOV and tons of exposure.

[frostynixon]

Thanks for sharing Olly. I wasn`t aware of the shelf. That`s really amazing what astrosciences/astrophotography discovered out there. First you learn about very discrete objects but if you delve in a little bit (maybe also alot) deeper than space starts to fill with all kinds of amazing objects. This "playground" is just so exciting!

[ollypenrice]

Very interesting..... never knew it existed. But if our MW has IFN, then its proabably a common thing.... along with tidal tails etc.

I can imagine it requiring ultra-dark skies, a big FOV and tons of exposure.

I'm going to guess that this nebulosity is from the MW, though I agree with your supposition. 

Olly

[johnrt]

I think part of our own Galaxy with M31 sitting behind, but what a bloomin' image that is!

[ollypenrice]

It is indeed. Hytham knows what he's doing.

Olly

[Mark72]

Olly,

I think it could at best confirm there is no such thing as background.  Here is M74 unknown to show much around it and yet there is a lot of IFN

http://www.astrobin.com/125254/

What Hytham's image shows might be IFN and with PI wavelets you are free to discover tidal streams everywhere. It looks suspiciously like super nova bow shock e.g. Barnard loop.

Seeing tidal stream or even IFN with unaided eye is totally ridiculous.

Mark

[Ewan]

After having seen a lot of members captures on here I have come to the conclusion that nearly every target in the night sky would exhibit some form of IFN, Cirrus, space dust call it what you will.

Most amateur imagers will image a target like M42 & capture the main neb & be happy with that, now look at Olly's 400 hour shot, nearly the entire image has some 'background' gradient to it.

Maybe this is a bit outlandish to say but I'm guessing if you took enough subs & long one's at that you would capture a lot more than you would ordinarily see with every target.

I spoke to Hytham a few times regarding imaging & he really does know his stuff, you only have to look at this post of his http://stargazerslounge.com/topic/215325-wide-field-ifn-wip/?hl=%2Bhytham#entry2306880  that & the link wxsatuser posted are very good examples.

It all depends if the imager is willing to put the time in to make new discoveries, that is after all how astronomy has evolved to what it is today & will continue to do so.

Just my two cents worth.

[Calypsob]

i think its important to point out astrophotographer hisayoshi katos work. He images in near mag 22 skies under the massively transparent mauna kea skies. I have asked several times about his process techniques and strange blending of exposures with a dslr but I must be honest, his methods still baffle me. One thing is for sure, any form of galactic cirrus is visible in his work due to processing technique and the appropriate fast optics and sensitive full frame dslr.  I think olly probably picked up this signsl as well, there is so much that it is easy to process out.  

 

https://m.flickr.com/#/photos/hiroc/6754827529/

 

 

[ollypenrice]

On 10/09/2016 at 05:04, Calypsob said:

  I think olly probably picked up this signsl as well, there is so much that it is easy to process out.  

 

https://m.flickr.com/#/photos/hiroc/6754827529/

 

 

Yes, you're probably right. I had a clear processing objective in my image, which was to reveal the outer glow around M31. I wasn't looking for IFN style nebulosity. I can go back to that project easily enough and look for it, though. Good fun!

Olly

[Fozzie]

Hi Olly

I know this is an oldish thread regarding the Andromeda Shelf, but it's Friday afternoon and I was curious and just doing a bit of looking around the subject and came across this thread called the M31 twist in deep sky forum.

http://www.deepskyforum.com/showthread.php?623-The-M31-quot-Twist-quot

Mel Bartles comments (number 10) in the thread that the shelf as he calls it is feature of the MW as he see's it.

Don't know if that helps to conclude what the Shelf structure is at all, but thought it might be relevant.

Thanks

Fozzie