Object of the Week August 20th, 2017 – NGC 7217

Object of the Week August 20^th, 2017 – NGC 7217

NGC7217
UGC11914
PGC68096
CGCG 494-2

Pegasus

Galaxy

RA 22 07 52.4
DEC 31 21 33
Mag 11.0

Size 3.9 x 3.2

Class (R)SA(r)ab

(sorry for the brevity. I am traveling for the eclipse and have limited internet connectivity)

NGC7217 was discovered in 1784 by William Herschel using his 18.7” speculum mirrored reflector giving it the notation “easily resolved”. Many online reports mark this object as “dim”, I feel it’s quite the opposite and makes for a fine view in an eyepiece.

NGC 7217 is a face on unbarred spiral 50Mly away in the constellation of Pegasus. Though its most outermost ring is the most prominent, NGC7217 actually contains 3 rings, 2 more inside the visible outer ring we can see in our scopes. Mind you, I’ve never seen the ring itself nor do I know of any reports. It is very disk like visually appearing much like a face on. In the eyepiece, the galaxy isn’t particularly difficult offering a very stellar like core with a dim halo. In larger scopes there can be some mottling that is observable in the outer disk/ring.

Give it a go and let us know!

Attachment 2632

Attachment 2633

The outer ring is visible as a wide, soft and better defined edge of the halo.

Not unusual because few elliptical galaxies with very bright core and large and bright halo looks like a ring because of contrast phenomena. But the rim of NGC 7217 is more clear and I noticed "not difficult" in my description. In my mind very important is the right EP to detect the ring. For me 2,8mm was the sweet spot.

27", 244x, NELM 6m5+, Seeing V (bad)
Attachment 2634

Great observation of the ring. The best I have so far is this, with 16": "At 225x, elongated slightly EW, concentrated, edges diffuse."

I liked this galaxy in my old 10 '' very bright and detailed, nucleus considerably bright, dusty halo. I have to see this again in my 16 ''

http://dibujodelcielonocturno.blogsp...7-pegasus.html


Roberto.

I hadn’t observed this galaxy before, and last night was a tremendous night to do so: a dark, clear, transparent and steady sky. I agree that it is definitely not “dim” by any means; indeed, it is a beautiful little galaxy at all magnifications. Lovely view at 90x - a small bright round glow wrapped in a very faint and narrow hazy halo, and framed in a triangle of faint stars, that itself lies off-centre in a raggedy-looking circle of seven brighter stars.

At 150x it is dominated by its small core which is very bright; and its halo appears as a fairly large gauzy glow - it’s like seeing a very bright faraway light cutting through a deep mist. At this magnification it is off-round - ever so slightly elongated east-west.

At 225x the bright core really dominates the view, but the gauzy appearance of its halo is more apparent (not gauzy enough to be anywhere near mottling; more like a somewhat concentrated haziness). The edges appear diffuse. No sign of a ring.