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Jimi Lowrey
October 7th, 2016, 03:41 PM
This week I was joined by Akarsh Simha for a observing run here at my observatory in Fort Davis. The highlight of this run for me was our observation of the dwarf galaxies Pisces A&B. This is a link to a paper were observations were made by the HST https://arxiv.org/abs/1607.03487 There are great HST images of Pisces A&B in this paper.

SDSS Pisces A
2283

Pisces A was seen as a extremely faint small glow with AV at 375X only a small percent of the time. It appeared only as faint brightening of the background. I was not sure I was seeing it but when I would slew the scope the faint glow would move with the star field. I was not sure at first that we would be able to see this dwarf but we were both sure of or observations. This galaxy is not in the local group but is in the local volume.

SDSS Pisces B
2284

Pisces B was much easier to see it was direct vision at 488X as a faint extended object with a slight brightening on one end . I was surprised that it was not more difficult as was Pisces A. I contacted the author of the paper(Eric Tollerud) and he was shocked that we could see these dwarf's with our eyes.

Uwe Glahn
October 8th, 2016, 03:45 PM
Nice catch Jimi and Akarsh. Objects are noted, I will give them a try.

Jimi Lowrey
October 8th, 2016, 05:59 PM
Uwe,

Pisces A&B were found on the GALFA-H I compact cloud catalog survey. The catalog was published in 2012.

I have no way of knowing but I would bet that Akarsh and my observations of these faint dwarfs were the fist visual observations of them. I would be surprised if anyone had tracked down these obscure objects before.

Uwe Glahn
December 1st, 2016, 04:42 PM
Got Pisces B.
Under good transparency and NELM around 7mag I could detect Pisces B without large problems. Faint glow was popping in and out of view with 293x with my 27-inch as a 1:2 N-S elongated smudge. Not steadily visible but a clearly brightening at the E side of a the neighborhood star. Looks a little bit larger than in the SDSS or DSS. With 419x glow became smaller, but still 1:2 N-S elongated.

Howard B
December 9th, 2016, 01:09 AM
Great observation Uwe, and I hope to give Pisces A and B a try with my scope soon. My notes from our views through Jimi's 48 inch:

Pisces A
"Pisces A is (a) rather large smutz barely brighter than the sky background. A definite sighting in both the 8mm (610x) and 13mm (375x) eyepieces. 21.39 SQM."

Pisces B
"Threshold object that I could barely detect. 8mm, 21.47 SQM."