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View Full Version : LEDA 3864456, an unknown E.E. Barnard discovery



Steve Gottlieb
July 7th, 2016, 05:08 PM
On the evening of June 17th 1890, E.E. Barnard shared the 36-inch dome at Lick Observatory with Sherbourne Wesley Burnham to search for d'Arrest's Comet. Barnard recorded in his logbook, "Saw at least 3 nebulae. One was much elongated and with perhaps a small one close following [no position estimated]. The other two were small and indefinite. One was between two stars."

Barnard made a simple sketch showing a nebulous object [galaxy] between two mag 9/11 stars oriented SE and NW and slightly closer to the fainter NW star - a perfect match with LEDA 3864456 = 2MASX J16215957+1224109, a 16th magnitude galaxy in Hercules. He later added (after returning to the 12-inch dome), "It is with the utmost difficulty that I can see the nebula with the 12-inch. It is vS and vF."

A second "nebula" was described as "small, pretty bright, round, is 35' +/- preceding this and 1' N". The next night Barnard observed in the big dome again (along with Burnham) and returned to these two objects with the 36-inch Clark refractor. This time he logged, "the [western] one precedes the other by 2min 21s (by watch) and is ½' N. The following is the one between the two stars." Using this offset, it's easy to identify the western galaxy as LEDA 1408945, another 16th magnitude galaxy.

Barnard never published these (along with many other) discoveries at Lick, so neither galaxy received an NGC/IC designation and today are only known by modern survey designations such as 2MASS and SDSS.

Using my 24-inch I took a look at LEDA 3864456 (16 21 59.6 +12 24 11, J2000) a week ago at the Golden State Star Party under SQM 21.7 skies. Using 322x and 375x, LEDA 3864456 appeared very faint, very small, round, ~12" diameter, visible nearly 100% of the time with averted vision and concentration. This tiny galaxy is situated between mag 9.9 SAO 102106 0.9' SE and a mag 13.9 star 0.5' NW.

I'm quite impressed this galaxy could be glimpsed with the Lick 12-inch Clark refractor (the derived SDSS magnitudes are roughly V = 15.6, B = 16.5) - but then again we're talking about E.E. Barnard. If anyone takes a look with a 12" to 18" scope, I'd be interested in hearing your results.

Norman
July 21st, 2016, 02:56 PM
Challenge taken!

Ivan Maly
July 21st, 2016, 09:45 PM
Norman, it will be interesting to know what you see in your Newtonian. I did see both of these Hyperleda objects with my 12" SCT, as communicated to the OP on another forum. #38... was pretty obvious as 7-digit PGC galaxies go and #14... (apparently only viewed through the 36" at Lick but I gave it a try anyway) was indeed difficult and I spent quite some time making certain of this observation. SQM 21.9+ skies, ZAO-IIs and all that jazz (although in the end humble Ethoses worked too)... Good luck and let us know.

Norman
July 22nd, 2016, 09:44 AM
Hi Ivan,

encouraging information Ivan :-) Congrats!
21,9-skies... gee... i´ll see what next weeks are comin up with - around 21,5 should be possible. Let´s see if the contrast of my new 0,98-mirror and 21% obstruction is able to even the disadvantage of the worse sky ;-)

CS,
Norman

Ivan Maly
July 22nd, 2016, 06:43 PM
We seem to be again on a favorable combination of the 18- and 6-month skyglow cycles here at geomagnetic latitude 52, with consistent night-to-night readings above 21.9. I think PGC 38... should not be very sensitive to the background brightness but 1408945 has a diffuse halo and small, seeing-dependent core. Also there is a Vm 16.9 star next to it that is also seeing-dependent in this aperture but can, potentially, be fused visually with the halo. I ascertained that the halo visible at more moderate magnifications does not extend to the star position, and was able to glimpse the core and the star simultaneously at higher power. This could be the most difficult visually discovered object, especially if Barnard saw the galaxy separately from the star.