Object of The Week April 7, 2019–NGC 3908 (Did Swift See IT ?)

[Jimi Lowrey]

NGC3908

LEO

RA
11 49 53
DEC
+12 11 09

MAG 14.9V

TYPE E

————————————————-
I have a new project I am collecting and observing galaxies that have a light travel time of 1 billion light years and plus in the NGC/IC catalog. I have been surprised that I have found so many I am up to 96 and still looking. I will post the list and my observations when I complete the project.

Now on to NGC 3908. NGC 3908 was found by Lewis Swift with his 16” Clark refractor on April 10th 1885 he reported it F vS R mbm. It has a light travel time of 1.1 billion light years according to the SDSS. The problem is Swift did not record a very accurate position. NGC 3908 is the only galaxy in the area that comes close to Swift’s position. DR Harold Corwin of NED thought that NGC 3908 was to dim for Swift to see and was not sure that it was the object Swift reported. (I hope Steve G will tell us more about this).

Now this is were you come in! I would like to here from you on DSF about your observations of NGC 3908. I am sure after observing NGC 3908 that Professor Swift could and Did see NGC 3908 in his 16”and I would really like to here what you think and read about your observations of NGC 3908 with it’s billion year old light.

NGC 3908 SDSS
3482

Please “Give it A Go”

[Jimi Lowrey]

Steve Gottlieb and me with Swift’s 16” Clark Refractor at Santa Clara CA
3485

3486

[Howard B]

Cool photos Jimi - maybe we should pass the hat around so they can get a new lens cap!

NGC 3908 is on my list to observe the next clear night, and your list of the most distant NGC and IC objects will make a wonderful observing project!

[Steve Gottlieb]

Unfortunately, there's not a lot of clues in this case -- as Jimi mentioned, Swift's description is simply "faint, very small, round, much brighter in the middle". Pretty generic stuff. Often, Swift referenced nearby stars in the field, which would have helped to establish the identification. But not in this case.

Swift's position falls on an empty piece of celestial real estate, but Jimi's galaxy (PGC 36967) is the nearest one -- about 7' north of Swift's position.

Could this be Swift's galaxy? Sure, the discrepancy in position is not unusual and his general description fits. But this galaxy is on the dim end of galaxies that Swift discovered (V = 14.8, B = 15.8 based on the SDSS photometry). Furthermore, Swift called his faintest discoveries "eF" (extremely faint), "eeF (extremely extremely faint) and even "eeef" (you get the idea). In the scheme of Swift's descriptions, "F" (faint) is actually not very difficult.

So, the important question is whether or not PGC 36967 is a difficult object in a 16"? If so, Swift would have called it "eeF" or something similar and probably not the object he discovered. If it’s a direct vision object in this aperture, that would support the identification NGC 3908 = PGC 36967, and Swift gets credit for another billion light year galaxy (his son discovered IC 1101).

Who is able to take on the test?