PDA

View Full Version : Object of the week October 1, 2023–IC 1756 and IC 1757 A chance alignment



Jimi Lowrey
October 2nd, 2023, 04:53 PM
IC 1757
Cetus
RA 01 57 11
Dec -00 28 25
MAG 15.7
Type E
Z= 0.080

IC 1756
Mag 15.3
Type EO
Z= 0.02239

————————————————
I have written an article that will be in the December Sky&Telescope Magazine about the 12 most distant galaxies that were found visually while looking through a telescope. The article is called the “Distant Dozen” The galaxies above are my favorite of the 12 distant galaxies in the article. What is interesting to me is the chance alignment of IC 1757 and IC 1756. IC 1756 lies at 310 million light years away while IC 1757 has a light travel time of a mind bending 1.06 Billion light years away. With a separation of 1.6’ this is truly a chance alignment. I also like this pair as I am a big fan of super thin galaxies.

5234

The pair was found by the Eagle eye visual observer E E Barnard at Lick observatory he did not record what telescope he used that night but it was probably the 36” refractor. He also did not record the discovery date.

My brief notes say “Now we are talking! a Edge on galaxy Right by a billion year light travel galaxy” They
appear on this night to be of equal brightness.

I hope you will give this unique pair a Go I look forward to hearing about your observations of this chance alignment pair. I also hope you will enjoy my article about the “Distant Dozen” in the December Sky&Telescope.

GIVE IT A GO
Good Luck and Great Viewing

Jimi Lowrey
October 3rd, 2023, 05:41 PM
This is a SDSS image of the pair

5235

Steve Gottlieb
October 4th, 2023, 03:02 AM
These observations were made with my 24" in late Sept. 2019 with an SQM reading of 21.3.

IC 1756: Very faint, edge-on 4:1 NNW-SSE, ~40"x10", low even surface brightness, no core. A mag 14 star is at the southeast edge and the galaxy is a dim streak extending mostly NNW from the star. A mag 13.7 star is 1.7' SW.

IC 1757: Extremely faint, very small, 10" diameter, low even surface brightness. Required careful averted vision to hold for an extended period. Situated just 1.5' E of brighter IC 1756.

Uwe Glahn
October 4th, 2023, 06:53 PM
Nice pair that I also visited in the past. I'm curious from where I had this object, maybe deepskyforum.com or a list from Steve?

Beside the sketch I add my comments of both galaxies with my 27".

IC 1756: faint but direct vision object, 3:1 - 4:1 elongated, no peaks or dust lane
IC 1757: round diffuse and laminar glow, steadily visible with averted vision

sketch: 27", 419x, NELM 6m5+, Seeing IV
5245
home (http://www.deepsky-visuell.de/Zeichnungen/IC1756_IC1757.htm)