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View Full Version : Object of the Week August 19, 2012 NGC 6907 And the Strange Case of NGC 6908



Jimi Lowrey
August 19th, 2012, 07:20 PM
NGC 6907 And The Strange Case of NGC 6908

Capricornus

20 25 06

-24 48 33

Type SB Galaxy

Mag 11.9


NGC 6907 is a beautiful one armed SB galaxy. I remember one night many years ago I was sweeping for Comets with my old 25" F/5 and I swept up this big and bright galaxy, it was the high light of the session and I often return to it. At MAG 11.9 this galaxy looks great in most scopes.

In 2007 Barry Madore of Carnegie observatories did near infrared imaging of the bright region in the north arm(NGC 6908) that was thought for 150 years to be a H II or a surface brighting in the arm. Madore thought that it might be a galaxy interacting with NGC 6907 and as it turned out he was right. NGC 6908 is a lenticular S0 galaxy at nearly the same velocity of NGC 6907 and is in a deep interaction with it. It is indeed strange that NGC 6908 was thought to part of NGC 6907 for 150 years and it took the advancement in imaging and modern telescopes to show that it is a separate galaxy.

Be sure to check out this beautiful interaction the next time you are under Dark Skies that took 150 years to figure out and




"GIVE IT A GO AND LET US KNOW"

GOOD LUCK AND GREAT VIEWING!


283

Steve Gottlieb
August 20th, 2012, 06:24 AM
NGC 6907 certainly deserves a little more love -- I'm glad you posted it as an OOTW!

Here's my last observation with my 18". I'm sure a smaller aperture will resolve the brighter arm...

18" (9/3/08): beautiful view at 280x using an 8mm Ethos. A large 2' "bar" is oriented E-W with a broad, weak concentration but suddenly rises to a very small, bright core and faint stellar nucleus. On the east side of the bar, a spiral arm is attached that hooks directly to the north and just begins to sweep clockwise around on the north side of the galaxy towards the west. There appears to a brightening (faint knot) near where the arm is attached to the bar. Off the west side is faint haze on the south side, but the arm structure is very weak. A mag 11.5 star lies 2.8' due east of center ,on line with the central bar.

Uwe Glahn
August 21st, 2012, 07:19 PM
Great object and cool story about the uneven pair.

I can serve with an old sketch with a 24" and 370x under alpine skies.

286