Monoceros Loop

[Robin]

Hi folks,

In this thread I've just learned about Monoceros Loop (VMT 10):
http://www.deepskyforum.com/showthread.php?1340-Object-of-the-Week-February-09-2020-WR-bubble-Sharpless-2-308

I did an internet search for this object, and it turned out to be really interesting. Please consider this image:
http://starimager.com/Image%20Gallery%20Pages/Hydrogen%20Alpha%20Images/monoceros%20loop_180%20nikon_hi%20res.htm

It seems to me that there are at least two different loops that look like supernova remnants (or some other kind of shells). Is anyone familiar with the physical nature of both of these loops?

One of these loops touches Rosette Nebula and includes a filament that is called "Monoceros Loop" in the Interstellarum Deep Sky Atlas, page 60, RA = 6h43m, DE = +6.5°. But there is a second loop around Cone Nebula and Hubble's Variable Nebula that looks like a more homogeneous shell (perhaps not a supernova remnant?).

@Jiri and others: I would love to read about your visual observations. :-)


Clear skies,

Robin

[j.gardavsky]

Hi folks,

In this thread I've just learned about Monoceros Loop (VMT 10):
http://www.deepskyforum.com/showthread.php?1340-Object-of-the-Week-February-09-2020-WR-bubble-Sharpless-2-308

I did an internet search for this object, and it turned out to be really interesting. Please consider this image:
http://starimager.com/Image%20Gallery%20Pages/Hydrogen%20Alpha%20Images/monoceros%20loop_180%20nikon_hi%20res.htm

It seems to me that there are at least two different loops that look like supernova remnants (or some other kind of shells). Is anyone familiar with the physical nature of both of these loops?

One of these loops touches Rosette Nebula and includes a filament that is called "Monoceros Loop" in the Interstellarum Deep Sky Atlas, page 60, RA = 6h43m, DE = +6.5°. But there is a second loop around Cone Nebula and Hubble's Variable Nebula that looks like a more homogeneous shell (perhaps not a supernova remnant?).

@Jiri and others: I would love to read about your visual observations. :-)


Clear skies,

Robin

Hello Robin,

I have only one sighting of the VMT-10 (SNR 206.5 -00.1): A wide streak pointing north, extension longer than in IDSA p.60
6" F/5 achro, EPs: Leica HC Plan S f=25mm, Leica L f=32mm, H-Beta (12nm), OIII (10nm)
Backyard (nominally Bortle 4), 30th March, 2019
Other objects observed on that night: Sh2-308 (W-R)

The VMT-10 has been pretty time consuming, and without having seen before the astrophoto you have linked, it can be easily overseen.

Thank you for introducing this object,
JG

[Uwe Glahn]

Hi Robin,

at the time I used the [OIII] image of A. Bringmann at planetarynebulae.net (http://planetarynebulae.net/EN/page_np.php?id=723) to search for StDr 13.
While I had a negative observation of the PN I could clearly see an edge N of the PN of VMT 10. Problem was the huge size of the object which doesn't allow an observation of the SNR as a whole object. Smaller aperture with larger fields are does benefit from that.

[j.gardavsky]

Hello all,

there is also a nice capture of the Monoceros Loop in https://www.cloudynights.com/topic/696980-snr-g205505-monoceros-loop/#entry10025489

Best,
Jiri

[Robin]

Hi Uwe and Jiri,

Thank you for your replies! So if I understand correctly, you observed two different segments of the SNR: North of Rosette Nebula (near that PN) and northeast of Rosette Nebula (extension of what is shown in IDSA).
It is really funny how one can get fooled by H-alpha images.. It took me a while to figure out that both images by A. Brinkmann show the exact same field. And on the image I linked above the SNR is of much smaller contrast than Cone nebula (which I have never seen with 12" aperture).

Clear skies,

Robin