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View Full Version : Object of the Week November 10, 2013 – NGC1300



Dragan
November 10th, 2013, 05:35 AM
NGC 1300
UGCA 66

Eridanus

RA 13 19 40.8
DEC -19 24 41

Type: Galaxy SB(rs)bc

Size: 5.9’ x 4.9’

Mag: 10.3

Discovered in 1835 by William Herschel, NGC 1300 is the embodiment of a face-on barred spiral galaxy. Lying approximately 61 million light years towards the constellation Eridanus, NGC1300 is a prominent member of the Eridanus Cluster, a galaxy cluster containing approximately 200 members.

During my research of this weeks object, I learned that NGC1300 contained a “grand design” spiral structure or “spiral disk”, a feature commonly observed in the cores of galaxies that contained a large prominent bar. (This is a feature visible in the attached HST pictures) Theory was that these spiral structures, within the core of a barred spiral galaxy, would feed gas from the bar to a black hole situated at the core of the host galaxy. The problem was that NGC1300 wasn’t believed to contain a blackhole. Early observations did not indicate a blackhole existed at the galaxy’s core. Why did 1300 contain this spiral structure so commonly associated with blackholes but not host a blackhole? Digging further I found that in 2005, a team of astronomers released a paper announcing the discovery of a blackhole. The paper revealed that NGC1300 contains a blackhole on the order of 66 million solar masses! So not only does NGC1300 have a blackhole, but it contains a supermassive blackhole! http://arxiv.org/ftp/astro-ph/papers/0502/0502573.pdf What I personally don't understand is how so many sources online still reflect the old theory of NGC1300 not containing a blackhole.

In the eyepiece, this weeks OOTW is always a spectacular sight. In my 25, both arms are visible with the bar being somewhat bright and elongated. I even tend to see some mottling. I have also found that the southern arm tends to be more prominent than the other. And though I’ve read reports of some observers having seen NGC1300 in scopes as little as 8” in aperture, I’m not certain what the smallest scope that is needed to make out any arms or bar.

One last note, being placed at -19 in declination makes it a decent target for mid latitude observers both north and south of the equator! So next time you’re out, be sure to give NGC1300 a good onceover.

And remember,

“Give it a go and let us know!
Good luck and great viewing!”

965
(DSS)

966
(DSS Invert)

967
(HST)

968
(HST Core)

Ivan Maly
November 10th, 2013, 02:13 PM
Actually a John Herschel discovery made from South Africa. I believe I have seen some of John Herschel's galaxies in that region of the sky but not this one.

Uwe Glahn
November 10th, 2013, 07:56 PM
Wonderful object Dragan,

unfortunately the object is very low in the sky here from Germany. That is why the galaxy is not to famous here...sad but true. I tried it with my 16" from an Alpine site and could easily see the both arms. I revisit the galaxy from Namibia 2009 and 2011 and what a burner especially in the 24".

16", 180x, NELM 7m+, Seeing II (Bieler Höhe, Austrian Alps)
http://www.deepsky-visuell.de/Zeichnungen/NGC1300.jpg
inverted version (http://www.deepsky-visuell.de/Zeichnungen/NGC1300.htm)

Dragan
November 10th, 2013, 08:31 PM
Hi Uwe,

It doesn't get exceptionally high here either but it does get high enough above the crud in the southern sky to make it a worthwhile visit. John Spack was out last night with average conditions and was able to see it in his 18". He described it over the phone to me as an elongated glow with some mottling. He was unable to discern the arms he said.

Unfortunately, I had to work and was unable to join him. :(

I did observe NGC1300 in Oct of 2009 with Jimi and the 48". Without it needing to be said, the view was astonishing as it was truly a fantastic sight!

Astrojensen
November 10th, 2013, 08:53 PM
I'll have to try it, but it doesn't get more than barely a hand's width above the horizon here from my norther outpost.


Clear skies!
Thomas, Denmark

Steve Gottlieb
November 12th, 2013, 05:50 PM
I'll throw in my notes with Jimi's 48-inch from a couple of years ago. I was hoping to get another look earlier this month in his scope to resolve some of the HII regions at higher power, but we didn't get around to NGC 1300.

I took a look at the preprint that Dragan referenced (thanks!) and the mass of the black hole the authors modeled is actually closer to 65 million solar masses.

48" f/4 (10/25/11): This prototype barred spiral was mesmerizing at 375x. Running roughly E-W through the center is a long bright bar, ~3' in length. The center is sharply concentrated with an intensely bright 1' core that continues to increase to a stellar nucleus. At the west end of the bar a fairly bright arm emerges and hooks back dramatically to the east (counterclockwise) to the north of the bar and continues to the NE end of the galaxy. The arm is brightest in the thick arc, oriented SW-NE, where it attaches to the bar. The central section of the arm to the north of the core is slightly fainter and then brightens slightly on its northeast end. A mag 15.5-16 star is superimposed in the gap between this arm and the core, 45" NE of center. The second arm emerges at the east end of the bar and is brightest initially in a fairly thick arc extending counterclockwise to the SW. This arm is slightly more separated from the core as it gracefully curves to the southwest side of the galaxy. The arms extend the overall size of the galaxy to 5'x3' WNW-ESE.

Dragan
November 12th, 2013, 07:32 PM
I took a look at the preprint that Dragan referenced (thanks!) and the mass of the black hole the authors modeled is actually closer to 65 million solar masses.



Good catch Steve. 6.6 x 10 to the 7th. (+ or -) I did read it as 66 million and meant to type it as so. Totally left off that second 6! *sigh*

Thanks for the correction!! I'll edit it now

akarsh
November 22nd, 2013, 11:08 AM
This was one of my first galaxy observations with my then newly acquired 17.5" scope, from south India. The galaxy would come high up from the 13 °N latitude, but I observed it very close to the horizon (because I didn't appreciate the importance of having objects high up back then). I later observed it through John T's 25" from central Texas a couple years ago. Oddly enough, in the 25" log, I just mention it. Here is a sketch from my old (2009) observation:

http://bas.org.in/~akarsh/Astrosketches/Dec_2009/NGC1300.png