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View Full Version : Object of The Week May 26, 2019-NGC 5609 (A Far out Galaxy)



Jimi Lowrey
May 26th, 2019, 05:06 PM
NGC 5609

Bootes

Ra 14 23 48 Dec +34 50 34

Type ?

Mag 15.6V

Z=0.10058 Light travel time 1.3 Billon light years.

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Hi all I am filling in for Dragan this week he is traveling.

NGC 5609 is one of the most distant galaxies in the NGC/IC catalog and so far it is the most distant that I have found and confirmed by the redshift that was found visually. It was found by Bindon Blood Stoney with Lord Parsons 72” reflector on the night of March 1, 1851. Blood Stoney turned the 72” to NGC 5614 (AKA Arp 178) on that night to map the spiral structure of NGC 5614. To his surprise he found the nebula NGC 5613,NGC 5615 and NGC 5609 all near NGC 5614.
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What makes NGC 5609 so interesting is how distant it is with a light travel time of 1.3 billion light years. So if you like ancient photons give it a go! I must admit that it is not much to look at my meager notes say that at 488X it is small round with a even surface brightness and is direct vision. But knowing that you are seeing billion year old light changes everything for me.
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If you want to see the most distant object in the NGC/IC catalog that was found visually and become a member of the Billion Light Year Galaxy Club “Give It A Go”. Good Luck and Great Viewing.

Paul Alsing
May 27th, 2019, 04:19 AM
Hi Jimi,

I was surprised that SkyTools 3 did not have NGC 5609 in its database, so I looked it up on a Google search to learn a little more... and found this Wiki article...

https://en.wikipedia.org/wiki/NGC_5609

... which says... "NGC 5609 is a spiral galaxy[3] located 1.3 billion light-years light-years away from Earth,[4] in the constellation Boötes.[2] It has the second largest redshift of any galaxy in the New General Catalogue. Only NGC 1262, another spiral galaxy has a higher redshift." So, I checked out the NGC 1262 page...

https://en.wikipedia.org/wiki/NGC_1262

... where it says... "NGC 1262 is a barred spiral galaxy[3] located in the constellation Eridanus.[4] NGC 1262 is the most distant object in the New General Catalogue [5] lying about 1.5 billion light-years away from Earth."

So, it seems that NGC 5609 is actually the second farthest NGC/IC object... but still, 1.3 billion light-years is still really ancient light, and worth pursuing...

Steve Gottlieb
May 27th, 2019, 05:24 AM
Hi Jimi,
...
So, it seems that NGC 5609 is actually the second farthest NGC/IC object... but still, 1.3 billion light-years is still really ancient light, and worth pursuing...

Maybe...

A 1993 redshift survey reported z = .1157, which corresponds to a light-travel time of 1.5 billion years (using H0 = 70, and other cosmology constants). But the later 1998 "Southern Sky Redshift Survey" reported the z as .0833, which corresponds to a light-travel time of only 1.1 billion years. So, clearly one of these sources is in error.

This galaxy must be a giant in either case, but if it's truly at 1.5 billion light years, its large apparent diameter (about 1.2'), would imply a whopping physical diameter of over 500 million light years. That would make it as large as NGC 6872 -- with those extremely stretched spiral arms. So, I'd place my bet on the 1.1 billion figure -- in which case, NGC 5609 is probably the most distant in the NGC (at this point).

Both redshifts are reported here (http://ned.ipac.caltech.edu/cgi-bin/datasearch?search_type=z_id&objid=8960&objname=NGC%201262&img_stamp=YES&hconst=73.0&omegam=0.27&omegav=0.73&corr_z=1&of=table) in NED.

Jimi Lowrey
May 27th, 2019, 01:07 PM
Paul, as Steve said there is a problem with the redshift reported for NGC 1262. I have time on the McDonald Observatory 107” in September to get a spectrum with the virus spectrograph to find out which if any of the redshift that NED has are correct. So as of now NGC 5609 is the most distant that can be Verified. If you look at a image of NGC 1262 It looks really big if it is at a light travel time of 1.5 billion light years.

I had DR Steve Odewahn at McDonald look at NGC 1262 reported redshifts in NED and he verified that there appeared to be a problem with the reported redshifts in NED. He also said the galaxy looked to be to large in images of it to be at 1.5 billion light years light travel time.

So stand by and I should have the answer in early October as to which galaxy is the most distant found visually. So by the data we have NOW NGC 5609 is on top.

Paul Alsing
May 28th, 2019, 03:50 AM
Thanks for the background checks, Steve & Jimi. I knew there might be more to the story.

Someone needs to update the Wiki page for NGC 1262 :>)