Faint structures streaming from LMC

[cazza132]

LMC + SMC - looks like there may have been a collision between the two. Could the LMC actually be a spiral galaxy? Full spectrum modded 6D, Siggy 35mm f1.4 at f2.2, ISO1600, 20s,60s & 180s, on lens vis+Ha (Spencer's).

[gregbradley]

You are breaking new ground here. I haven't seen what appear to be tidal streams coming off LMC before.

Greg.

[cazza132]

I haven't seen them before either. I was nearly going to dismiss them as cloud bombs, but they showed up in shots from 3 different astro shoots. Couldn't find anything on the internet either. I always thought the LMC & SMC were elliptical galaxies.

[Nico13]

Nice work there Cazza,
I do recall reading somewhere that the LMC is classified as a Barred Spiral which surprised me but can't recall where at the moment.

PS. Just checked it was in Sky Safari Pro on the iPad that refers to it as a Spiral Galaxy

[alpal]

That's a very interesting pic.

You can make out the distorted spiral structure.

[dvj]

Not unknown to professionals, but I don't think I've seen many amateur images of this structure called the Magellanic Stream. Extremely faint. You must have shooting from an extremely dark site.

http://en.wikipedia.org/wiki/Magellanic_Stream

And here is a deep, inverted stretch of the area...

http://www.flickr.com/photos/hiroc/4716268091/in/photostream/

[Octane]

I can't remember who it was, but, someone from Perth posted images about 5 years ago showing the same tidal stream structure, too.

It only shows up in deep exposures.

Beautiful stuff. :)

H

[ZeroID]

Fascinating and stunning image. What was total exposure time ?

[alexch]

Hi Troy,

Indeed LMC is a barred (peculiar) spiral galaxy and its spiral structure was confirmed by Shapley in 1931. In one of the early papers - "Studies of the Magellanic Clouds (http://articles.adsabs.harvard.edu/cgi-bin/nph-iarticle_query?1955AJ.....60..126D& data_type=PDF_HIGH&whole_paper=YES& type=PRINTER&filetype=.pdf)", De Vaucouleurs (1955) noted the faint 20-degree long filament stretching out of the LMC (see Plate II in the paper (http://tinyurl.com/kdeb8su)). De Vaucouleurs estimated the luminosity of this filament at 25/26 mag/arcsec^2 - rather faint. I overlaid your inverted and stretched mage with the Plate II from the paper (http://tinyurl.com/kdeb8su) and the long LMC streamer does match. Proper calibration would improve your data, but some of that faint stuff is indeed real. I attached a small animated gif and larger version is here:
https://dl.dropboxusercontent.com/u/26867757/iis/Magellenic-Clouds140326.gif

Trying to find out about the possible collision between LMC and SMC I came across this paper (http://articles.adsabs.harvard.edu/cgi-bin/nph-iarticle_query?1994A%26A...291..743 H&data_type=PDF_HIGH&whole_paper=YE S&type=PRINTER&filetype=.pdf) by Heller and Rohlfs (1994) where they model orbits of LMC and SMC and suggest that a close collision between the two occurred about 500 Million years ago. Later studies suggest an off center, moderate to highly-inclined collision between the SMC and the LMC's disk that took place between 100 and 200 Million years ago (Casetti-Dinescu et al. 2012 (http://arxiv.org/pdf/1205.0989.pdf)).

Cheers,
Alex

[atalas]

I'm sure Ive seen the tidal tale somewhere before but still very nice Pic.

[strongmanmike]

Given what Alex has done there Troy it looks like your data is relatively sound, in fact I think you have revealed more extensions and more detail than the Aero Ekta lens did. The individual circular frames of old B&W film data look to have suffered from vignetting and thus without the modern technique of flats available to them and after mozaicing the circular frames together the faint extensions are probably not complete..?

Nice work and another example of why THIS (http://www.pbase.com/strongmanmike2002/image/153087957/original) may well not make me a deluded emperor ;)

MIke

[astroron]

Hi Cazza, you may wish to go into this thread to get some really good info on the LMC.
http://www.iceinspace.com.au/forum/showthread.php?p=1068216#post106821 6
Some very good observers and knowledgable people there.:)
Cheers:thumbsup:

[cazza132]

Wow - cheers, thank you Alex! Interesting info too.

[cazza132]

Thanks for the heads up Ron. Quite a detailed read.

[cazza132]

Thanks Mike, atalas, ZeroID, Octane, dvj, alpal and Nico13. 4x180s, 4x60s and 4x20s subs, 35mm, f2.2, ISO1600.

[madbadgalaxyman]

As mentioned by Ron, we are discussing the structure and history of the LMC in the "Observation reports" forum.

I have just posted a link to a slide presentation on the nature of Magellanic Spiral galaxies (= the Hubble type SBd), which is the accepted galaxy classification of the LMC.
I have also given some more information in my recent post about the general structure of the LMC .

[madbadgalaxyman]

Up-do-date info about the LMC and SMC can be found, in truly massive quantities, in the IAU Symposium S256:
http://journals.cambridge.org/action/displayIssue?iid=5005528

Get ready to expand your brain drastically, as the information content here is absolutely massive!
I think many of these are pretty hard papers...... certainly much tougher to read than the early papers written in the 1950s to 1970s on the two magellanic clouds.

[alexch]

No worries - your image is a nice work! It would be interesting to know if the streamers are more prominent in H-alpha or visual subs.

[Phil Hart]

Impressive image Troy and nicely processed. A surprising result given the relatively short exposure times. I hadn't recorded anything obvious on previous attempts at this but clearly I'll have to give it another go with the newer gear. You've composed the two clouds very nicely as well. :thumbsup:

Phil

[Shiraz]

:thumbsup: fascinating result Troy. looks like f2 helps with deep imaging

[MLParkinson]

Back in October 2013 I recorded an RGB image sequence of the LMC at Wiruna, Central Tablelands (>1000 m ASL). The sky at Wiruna can sometimes be very dark, except toward the South East (Sydney).

Here are low-resolution super-stretched versions of the original images. These noisy images show the spiral arms nicely, as well as what I imagine to be bow waves of star formation triggered by the LMC ramming into the halo of neutral hydrogen gas, dust and other dark matter surrounding the Milky Way.

Technical Specs: Canon Astro 50D with EXcooler, ISO 3200, 25 x 4-minute exposures, 100 mm f/2 Lens set at f/5.6.

[madbadgalaxyman]

Murray,

Certainly, your extremely interesting Deep Image shows a dramatically different LMC from the one we can see in short exposures.

Undoubtedly, the bar is way off-centre in the overall stellar distribution of this galaxy.

The pros have made various attempts to image the Mag. Clouds at great depth, for example:
http://adsabs.harvard.edu/full/1991IAUS..148..453I

http://arxiv.org/abs/1008.3727

In our discussion of the structure of the LMC in the recent "observation reports" forum, I presented an image showing the distribution of the red giant stars that define the halo of the LMC;
the bar looks off-centre, but not as far off centre.

Given the complex history of the LMC/SMC/MW system, and ongoing controversies as to how these galaxies evolved and changed with time, it is remarkable that few attempts have been made to really image as deep as possible on the LMC/SMC system.

cheers, Robert

[SkyViking]

A very interesting and beautiful image of the two clouds and their environment. The streamers are really standing out and seem to correlate well with previous data. You've done an awesome job at revealing these faint structures!