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IC 5350 - 5386 ← NGC Objects: NGC 1 - 49 → NGC 50 - 99
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Page last updated Aug 12, 2017

NGC 4 (= PGC 212468)
Discovered (Nov 29, 1864) by
Albert Marth
A magnitude 15.9 lenticular galaxy (type S0/a?) in Pisces (RA 00 07 24.4, Dec +08 22 26)
Historical Identification: Per Dreyer, NGC 4 (= GC 5081, Marth #2, 1860 RA 00 00 16, NPD 82 23) is "extremely faint". The position precesses to RA 00 07 26.7, Dec +08 23 46, over an arcmin north northeast of the galaxy listed above, but there is nothing else nearby and the offset is similar to that of NGC 3 (observed by Marth on the same night), so the identification is certain. However (per Corwin), at one time LEDA listed PGC 620 as NGC 4 because the catalogers did not realize that Marth could see an object as faint as PGC 212468; but Marth was using a telescope of 48 inches aperture (second only to Lord Rosse's 72 inch Leviathan at the time), and he really could see a 16th magnitude galaxy. The error in the LEDA database has been corrected, but awareness of the correction is not universal; so for any search the PGC 212468 designation or its coordinates should be used to ensure an accurate identification of NGC 4, and its incorrect identification as PGC 620 is discussed immediately below as a warning about such things.
Historical Note: The NGC entry is copied directly from Lassell's 1866 paper about observations at Malta, which included Marth's discoveries.
Physical Information: NGC 4's apparent size is about 0.6 by 0.15 arcmin (from the images below), but its distance is unknown, so its physical size is also unknown.
SDSS image of region near lenticular galaxy NGC 4, also showing NGC 3 and NGC 7840
Above, a 12 arcmin wide SDSS image centered on NGC 4, also showing NGC 3 and 7840
Below, a 0.6 arcmin wide closeup of the galaxy
SDSS image of lenticular galaxy NGC 4
Below, a 12 arcmin wide SDSS image centered on NGC 4; also shown are NGC 3 and 7840, and PGC 73256
SDSS image of region near lenticular galaxy NGC 4, also showing NGC 3, NGC 7840 and PGC 73256

PGC 620 (not =
NGC 4)
Not an NGC object but listed here since sometimes misidentified as NGC 4
A magnitude 17(?) spiral galaxy (type (R)SAB(rs)a? pec) in Pisces (RA 00 08 18.9, Dec +08 07 16)
Historical Misidentification: As noted in the entry for NGC 4, PGC 620 is sometimes misidentified as that object; so the purpose of this entry is to provide a warning about that.
Physical Information: Based on a recessional velocity of 5320 km/sec (and H0 = 70 km/sec/Mpc), PGC 620 is about 245 to 250 million light years away. Given that and its apparent size of about 0.55 by 0.45 arcmin (from the images below), it is about 40 thousand light years across. Its bright core suggests that it might be a Seyfert galaxy.
SDSS image of region near spiral galaxy PGC 620, which is sometimes misidentified as NGC 4
Above, a 12 arcmin wide SDSS image centered on PGC 620
Below, a 0.75 arcmin wide SDSS image of the galaxy
SDSS image of spiral galaxy PGC 620, which is sometimes misidentified as NGC 4

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IC 5350 - 5386 ← NGC Objects: NGC 1 - 49 → NGC 50 - 99