Celestial Atlas
(NGC 3450 - 3499) ←     NGC Objects: NGC 3500 - 3549     → (NGC 3550 - 3599)
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Page last updated Aug 24, 2015
Completed all original NGC entries
WORKING: Add positions/physical data (per Steinicke)
WORKING: Check existing pix for size, quality

NGC 3500 (= PGC 33277)
Discovered (Apr 2, 1801) by
William Herschel
A 14th-magnitude spiral galaxy (type Sab) in Draco (RA 11 01 52, Dec +75 12 05)
Historical Identification: Per Dreyer, NGC 3500 (= GC 2284 = WH III 967 = GC 2285 = WH III 968, 1860 RA 10 55 10, NPD 13 27.2) is "{III 967 = very faint, III 968 = extremely faint} double nebula, very near (Place very questionable)".
Discovery Notes: One of a multitude of objects observed by Herschel with his telescope misaligned with the meridian, leading to large errors in the position. A short discussion here and a lengthy one elsewhere (link?) explain the situation in detail.
Physical Information: Based on recessional velocity of 7400 km/sec, about 330 million light years away (although another recessional velocity measurement of 3465 km/sec would yield only half (!) that distance). Considered to be a member of the NGC 3523 group of galaxies, in which case the 7000+ km/sec recessional velocity for the other two galaxies suggests that the larger recessional velocity and distance are more accurate. Given that and apparent size of 1.3 by 0.6 arcmins, about 120 thousand light years in diameter. Note: Wikisky incorrectly shows NGC 3465 if NGC 3500 is entered. However, using the PGC 33277 designation shows the correct object.
Wikisky image of NGC 3500
Above, closeup of NGC 3500
Below, an approximately 15 arcmin wide region centered on the galaxy
Wikisky image of region around NGC 3500

NGC 3501 (= PGC 33343)
Discovered (Apr 23, 1881) by
Édouard Stephan
A 13th-magnitude spiral galaxy (type Scd) in Leo (RA 11 02 47, Dec +17 59 22)
Historical Identification: Per Dreyer, NGC 3501 (Stephan list XI (#10), 1860 RA 10 55 22, NPD 71 15.3) is "very faint, much extended north-south, gradually brighter middle, 3 arcmin long".
Physical Information: An edge-on spiral galaxy, paired with NGC 3507. Based on recessional velocity of 1130 km/sec, about 50 million light years away, in fair agreement with redshift-independent distance estimates of 65 to 85 million light years. Given that and apparent size of 4.4 by 0.55 arcmins, about 65 thousand light years in diameter.
Wikisky SDSS image of NGC 3501
Above, closeup of NGC 3501
Below, an approximately 15 arcmin wide region centered on the galaxy
Wikisky SDSS image of region around NGC 3501

NGC 3502 (=
NGC 3479)
Discovered (1886) by Ormond Stone (and later listed as NGC 3479)
Discovered (1886) by Francis Leavenworth (and later listed as NGC 3502)
Historical Identification: Per Dreyer, NGC 3502 (Leavenworth list I (#181), 1860 RA 10 55 30, NPD 104 12.3) is "extremely faint, pretty large, irregularly round, gradually a little brighter middle".
Physical Information:

NGC 3503
Discovered (Apr 1, 1834) by
John Herschel
Historical Identification: Per Dreyer, NGC 3503 (= GC 2286 = JH 3311, 1860 RA 10 55 33, NPD 149 05.8) is "3 small (faint) stars of 10th magnitude in very faint nebula".
Physical Information:

NGC 3504
Discovered (Apr 11, 1785) by
William Herschel
Also observed (date?) by John Herschel
Historical Identification: Per Dreyer, NGC 3504 (= GC 2287 = JH 810 = WH I 88, 1860 RA 10 55 35, NPD 61 16.5) is "bright, large, extended, much brighter middle and nucleus, partially resolved (some stars seen), preceding (western) of 2", the other being NGC 3512.
Physical Information:

NGC 3505 (=
NGC 3508 = IC 2622)
Discovered (Dec 31, 1785) by William Herschel (and later listed as NGC 3508)
Also observed (date?) by John Herschel (and later listed as NGC 3508)
Discovered (May 7, 1836) by John Herschel (and later listed as NGC 3505)
Discovered (Jan 14, 1898) by Lewis Swift (and later listed as IC 2622)
Historical Identification: Per Dreyer, NGC 3505 (= GC 2288 = JH 3312, 1860 RA 10 55 50, NPD 104 44.4) is "pretty faint, small, round, gradually a little brighter middle, 14th magnitude star near".
Physical Information:

NGC 3506
Discovered (Mar 11, 1784) by
William Herschel
Also observed (date?) by John Herschel
Historical Identification: Per Dreyer, NGC 3506 (= GC 2289 = JH 811 = WH III 22, 1860 RA 10 55 54, NPD 78 10.4) is "very faint, considerably small, round, very gradually very little brighter middle".
Physical Information:

NGC 3507 (= PGC 33390)
Discovered (Mar 14, 1784) by
William Herschel
Also observed (date?) by John Herschel
A 13th-magnitude spiral galaxy (type SB(s)b) in Leo (RA 11 03 25, Dec +18 08 08)
Historical Identification: Per Dreyer, NGC 3507 (= GC 2290 = JH 812 = WH IV 7, 1860 RA 10 55 58, NPD 71 06.7) is "considerably faint, pretty large, round, suddenly brighter middle small star, 9th magnitude star attached 25°".
Physical Information: A face-on barred spiral, paired with NGC 3501. Based on recessional velocity of 980 km/sec, about 45 million light years away, in fair agreement with a redshift-independent distance estimate of 65 million light years. Given that and apparent size of 3.4 by 2.9 arcmins, about 45 thousand light years in diameter.
Wikisky SDSS image of NGC 3507
Above, closeup of NGC 3507
Below, an approximately 15 arcmin wide region centered on the galaxy
Wikisky SDSS image of region around NGC 3507

NGC 3508 (=
NGC 3505 = IC 2622)
Discovered (Dec 31, 1785) by William Herschel (and later listed as NGC 3508)
Also observed (date?) by John Herschel (and later listed as NGC 3508)
Also observed (date?) by Herbert Howe (while listed as NGC 3508)
Discovered (May 7, 1836) by John Herschel (and later listed as NGC 3505)
Discovered (Jan 14, 1898) by Lewis Swift (and later listed as IC 2622)
Historical Identification: Per Dreyer, NGC 3508 (= GC 2291 = JH 814 = WH II 507, 1860 RA 10 56 04, NPD 105 32.1) is "faint, {per WH small, per JH very large}, brighter middle, star to northeast involved".
The second IC adds (per Howe) "is small, and the star half an arcmin northeast is not involved".
Physical Information:

NGC 3509
Discovered (Dec 30, 1786) by
William Herschel
Historical Identification: Per Dreyer, NGC 3509 (= GC 2292 = WH III 598, 1860 RA 10 56 05, NPD 84 28.3) is "extremely faint, small, a little extended?"
Physical Information:

NGC 3510
Discovered (Apr 11, 1785) by
William Herschel
Also observed (date?) by John Herschel
Historical Identification: Per Dreyer, NGC 3510 (= GC 2293 = JH 813 = WH II 365, 1860 RA 10 56 06, NPD 60 21.7) is "faint, large, considerably extended, 7th magnitude star 8 arcmin distant at position angle 310°".
Physical Information:

NGC 3511
Discovered (Dec 21, 1786) by
William Herschel
Looked for but not seen (1898) by Robert Innes
Historical Identification: Per Dreyer, NGC 3511 (= GC 2294 = WH V 39, 1860 RA 10 56 27, NPD 112 21.3) is "very faint, very large, much extended".
The second IC adds "NGC 3511 = V.39. Not found by Innes, while 3513 = V.40 (same description) was well seen (M.N., lix. p. 339)".
Physical Information:

NGC 3512
Discovered (Apr 11, 1785) by
William Herschel
Also observed (Apr 19, 1832) by John Herschel
Historical Identification: Per Dreyer, NGC 3512 (= GC 2295 = JH 815 = WH II 366, 1860 RA 10 56 27, NPD 61 12.7) is "faint, pretty small, round, pretty gradually brighter middle, following (eastern) of 2", the other being NGC 3504.
Physical Information:

NGC 3513
Discovered (Dec 21, 1786) by
William Herschel
Also obsearved (1898) by Robert Innes
Historical Identification: Per Dreyer, NGC 3513 (= GC 2296 = WH V 40, 1860 RA 10 56 44, NPD 112 29.3) is "very faint, very large, much extended".
The second IC adds "NGC 3511 = V.39. Not found by Innes, while 3513 = V.40 (same description) was well seen (M.N., lix. p. 339)".
Physical Information:

NGC 3514
Discovered (Mar 22, 1835) by
John Herschel
Historical Identification: Per Dreyer, NGC 3514 (= GC 2297 = JH 3313, 1860 RA 10 56 50, NPD 108 01.7) is "very faint, pretty large, round, very gradually very little brighter middle".
Physical Information:

NGC 3515
Discovered (Apr 20, 1882) by
Édouard Stephan
Historical Identification: Per Dreyer, NGC 3515 (Stephan list XII (#41), 1860 RA 10 57 01, NPD 61 01.2) is "very faint, small, round, several extremely faint stars involved".
Physical Information:

NGC 3516
Discovered (Apr 3, 1785) by
William Herschel
Also observed (date?) by John Herschel
Historical Identification: Per Dreyer, NGC 3516 (= GC 2298 = JH 816 = WH II 336, 1860 RA 10 57 02, NPD 16 41.4) is "pretty bright, very small, irregularly round, pretty suddenly much brighter starlike middle".
Physical Information:

NGC 3517
Discovered (Apr 8, 1793) by
William Herschel
Also observed (date?) by John Herschel
Historical Identification: Per Dreyer, NGC 3517 (= GC 2299 = JH 817 = WH II 884, 1860 RA 10 57 13, NPD 32 43.5) is "extremely faint, small, round, very gradually brighter middle".
Physical Information:

NGC 3518 (=
NGC 3110 = NGC 3122)
Discovered (Mar 5, 1785) by William Herschel (and later listed as NGC 3122)
Discovered (Mar 17, 1884) by Édouard Stephan (and later listed as NGC 3110)
Discovered (Dec 31, 1885) by Ormond Stone (and later listed as NGC 3518)
Historical Identification: Per Dreyer, NGC 3518 (Leavenworth list I (#182), 1860 RA 10 57 30, NPD 95 48.3) is "extremely faint, extremely small, a little extended (110°)".
Discovery Notes: Although Dreyer refers to Leavenworth's list I, the paper was actually published by Stone, and although most of the observations were done by Leavenworth, some were done by other observers, as in this case.
Physical Information:

NGC 3519
Discovered (Mar 14, 1834) by
John Herschel
Historical Identification: Per Dreyer, NGC 3519 (= GC 2300 = JH 3314, 1860 RA 10 58 19, NPD 150 36.6) is a "cluster, pretty rich, pretty compressed".
Physical Information:

NGC 3520
Discovered (1886) by
Francis Leavenworth
Historical Identification: Per Dreyer, NGC 3520 (Leavenworth list II (#431), 1860 RA 10 58 37, NPD 107 11.4) is "extremely faint, very small, irregularly round, gradually brighter middle, several very faint stars involved".
Physical Information:

NGC 3521
Discovered (Feb 22, 1784) by
William Herschel
Also observed (date?) by John Herschel
Historical Identification: Per Dreyer, NGC 3521 (= GC 2301 = JH 818 = WH I 13, 1860 RA 10 58 38, NPD 89 16.9) is "considerably bright, considerably large, much extended 140°±, very suddenly much brighter middle and nucleus".
Physical Information:

NGC 3522
Discovered (Apr 26, 1883) by
Lewis Swift
Historical Identification: Per Dreyer, NGC 3522 (Swift list III (#59), 1860 RA 10 58 55, NPD 69 09.7) is "pretty faint, very small, a little extended".
Physical Information:

NGC 3523 (= PGC 33367)
Discovered (Apr 2, 1801) by
William Herschel
A 13th-magnitude spiral galaxy (type Sbc) in Draco (RA 11 03 06, Dec +75 06 57)
Historical Identification: Per Dreyer, NGC 3523 (= GC 2302 = WH II 904, 1860 RA 10 59 05, NPD 13 33.3) is "faint, pretty large, a little brighter middle (place doubtful)".
Discovery Notes: One of a multitude of objects observed by Herschel with his telescope misaligned with the meridian, leading to large errors in the position. A short discussion here and a lengthy one elsewhere (link?) explain the situation in detail.
Physical Information: The brightest of three galaxies in the NGC 3523 group (consisting of NGC 3523, 3500, and 3465). Based on recessional velocity of 7165 km/sec, about 320 million light years away. Given that and apparent size of 1.5 by 1.5 arcmin, about 140 thousand light years in diameter.
Wikisky image of NGC 3523
Above, closeup of NGC 3523
Below, an approximately 15 arcmin wide region centered on the galaxy
Wikisky image of region around NGC 3523

NGC 3524
Discovered (Mar 11, 1784) by
William Herschel
Also observed (date?) by John Herschel
Historical Identification: Per Dreyer, NGC 3524 (= GC 2303 = JH 819 = WH III 23, 1860 RA 10 59 14, NPD 77 51.4) is "faint, small, a little extended, pretty suddenly brighter middle, 2 stars to northwest in line".
Physical Information:

NGC 3525 (=
NGC 3497 = NGC 3528 = IC 2624)
Discovered (Mar 8, 1790) by William Herschel (and later listed as NGC 3497)
Discovered (Mar 22, 1835) by John Herschel (and later listed as NGC 3528)
Discovered (1886) by Ormond Stone (and later listed as NGC 3525)
Discovered (Apr 11, 1898) by Lewis Swift (and later listed as IC 2624)
Historical Identification: Per Dreyer, NGC 3525 (Ormond Stone list I (#183), 1860 RA 10 59 30, NPD 108 42.3) is "faint, pretty small, gradually brighter middle and nucleus".
Physical Information:

NGC 3526 (=
NGC 3531)
Discovered (Mar 25, 1865) by Albert Marth (and later listed as NGC 3526)
Also observed (date?) by Rudolf Spitaler (and later listed as NGC 3526)
Discovered (Apr 27, 1881) by Edward Holden (and later listed as NGC 3531)
Historical Identification: Per Dreyer, NGC 3526 (= GC 5546, Marth 215, 1860 RA 10 59 40, NPD 82 05) is "extremely faint, very much extended, position angle 50°±".
The first IC notes "3531 to be struck out, is = 3526 (per Spitaler)"; so the identity of the two listings has been known for more than a century.
Physical Information:

NGC 3527
Discovered (Apr 11, 1785) by
William Herschel
Also observed (date?) by John Herschel
Historical Identification: Per Dreyer, NGC 3527 (= GC 2304 = JH 820 = WH III 350, 1860 RA 10 59 41, NPD 60 43.6) is "extremely faint, small, 10th magnitude star 60 arcsec to west".
Physical Information:

NGC 3528 (=
NGC 3497 = NGC 3525 = IC 2624)
Discovered (Mar 8, 1790) by William Herschel (and later listed as NGC 3497)
Discovered (Mar 22, 1835) by John Herschel (and later listed as NGC 3528)
Discovered (1886) by Ormond Stone (and later listed as NGC 3525)
Discovered (Apr 11, 1898) by Lewis Swift (and later listed as IC 2624)
Historical Identification: Per Dreyer, NGC 3528 (= GC 2305 = JH 3316, 1860 RA 11 00 17, NPD 108 43.1) is "faint, small, round, pretty suddenly a little brighter middle, preceding (western) of 2", the other being NGC 3529.
Physical Information:

NGC 3529 (=
IC 2625)
Discovered (Mar 22, 1835) by John Herschel (and later listed as NGC 3529)
Discovered (Apr 11, 1898) by Lewis Swift (and later listed as IC 2625)
Historical Identification: Per Dreyer, NGC 3529 (= GC 2306 = JH 3317, 1860 RA 11 00 20, NPD 108 47.3) is "extremely faint, small, round, very little brighter middle, following (eastern) of 2", the other being NGC 3528.
Physical Information:

NGC 3530
Discovered (Apr 8, 1793) by
William Herschel
Also observed (date?) by John Herschel
Historical Identification: Per Dreyer, NGC 3530 (= GC 2307 = JH 821 = WH III 915, 1860 RA 11 00 21, NPD 32 01.5) is "very faint, small, round, pretty gradually brighter middle".
Physical Information:

NGC 3531 (=
NGC 3526)
Discovered (Mar 25, 1865) by Albert Marth (and later listed as NGC 3526)
Also observed (date?) by Rudolf Spitaler (and later listed as NGC 3526)
Discovered (Apr 27, 1881) by Edward Holden (and later listed as NGC 3531)
Historical Identification: Per Dreyer, NGC 3531 (Holden (#3), 1860 RA 11 00 22, NPD 82 32.5) is "extended 50°, 11th magnitude star at southwestern end (equal to (GC) 5546?)" 5546 being NGC 3526, so Dreyer suspected right from the start that NGC 3531 was a duplicate of Marth's observation. This was confirmed in the first IC, which adds "to be struck out, is = 3526 (per Spitaler)", so the identity of the two listings has been known for more than a century.
Physical Information: Given the duplicate entry, see NGC 3526 for anything else.

NGC 3532
Discovered (1751) by
Nicolas Lacaille
Also observed (Apr 27, 1826) by James Dunlop
Also observed (date?) by John Herschel
Historical Identification: Per Dreyer, NGC 3532 (= GC 2308 = JH 3315, Lacaille II.10, Dunlop 323, 1860 RA 11 00 34, NPD 147 55.0) is "A very remarkable object, a cluster, extremely large, round, a little compressed, stars from 8th to 12th magnitude".
Physical Information:

NGC 3533
Discovered (Apr 22, 1835) by
John Herschel
Historical Identification: Per Dreyer, NGC 3533 (= GC 2309 = JH 3318, 1860 RA 11 00 45, NPD 126 25.0) is "most extremely faint, very small (faint) star attached".
Physical Information:

NGC 3534
Discovered (Mar 18, 1869) by
Otto Struve
Historical Identification: Per Dreyer, NGC 3534 (= GC 5547, Otto Struve, 1860 RA 11 01 08, NPD 62 37) is "very faint, 9th magnitude star 3 arcmin to northwest".
Physical Information:

NGC 3535
Discovered (Apr 18, 1784) by
William Herschel
Also observed (date?) by John Herschel
Historical Identification: Per Dreyer, NGC 3535 (= GC 2310 = JH 823 = WH III 111, 1860 RA 11 01 17, NPD 84 24.8) is "considerably faint, very small, round, brighter middle, mottled but not resolved".
Physical Information:

NGC 3536
Discovered (Dec 24, 1827) by
John Herschel
Historical Identification: Per Dreyer, NGC 3536 (= GC 2311 = JH 822, 1860 RA 11 01 19, NPD 60 47.2) is "faint, small, round, brighter middle".
Physical Information:

NGC 3537
Discovered (Feb 7, 1878) by
Wilhelm Tempel)
Also observed (1880) by Andrew Common
Historical Identification: Per Dreyer, NGC 3537 (Tempel list I (#30) & list V (#8/9), Common, 1860 RA 11 01 25, NPD 99 30.1) is "very faint, small, very faint star involved".
Physical Information:

NGC 3538
Discovered (Sep 15, 1866) by
Heinrich d'Arrest
Historical Identification: Per Dreyer, NGC 3538 (= GC 5548, d'Arrest, 1860 RA 11 01 28, NPD 13 40.6) is "very faint, pretty large, 17th magnitude star near".
Physical Information:

NGC 3539 (= PGC 33799)
Discovered (Apr 13, 1831) by
John Herschel
A magnitude 14.6 lenticular galaxy (type S0/a?) in Ursa Major (RA 11 09 08.8, Dec +28 40 21)
Historical Identification: Per Dreyer, NGC 3539 (= GC 2312 = JH 825, 1860 RA 11 01 31, NPD 60 34.5) is "extremely faint". The position precesses to RA 11 09 05.8, Dec +28 40 03, only 0.7 arcmin west southwest of the galaxy listed above and there is nothing else nearby, so the identification is certain.
Physical Information: Based on a recessional velocity of 9705 km/sec, a straightforward calculation indicates that NGC 3539 is about 450 million light years away. However, for objects at such distances we should take into account the expansion of the Universe during the time it took their light to reach us. Doing that shows that the galaxy was about 435 million light years away at the time the light by which we see it was emitted, about 440 million years ago (the difference between the two numbers being due to the expansion of the intervening space during the light-travel time). Given that and its apparent size of 1.1 by 0.25 arcmin, the galaxy is about 140 thousand light years across.
SDSS image of region near lenticular galaxy NGC 3539
Above, a 12 arcmin wide SDSS image of NGC 3539
Below, a 1.2 arcmin wide SDSS image of the galaxy
SDSS image of lenticular galaxy NGC 3539

NGC 3540 (=
NGC 3548)
Discovered (Mar 11, 1831) by John Herschel (and later listed as NGC 3540)
Discovered (Feb 7, 1832) by John Herschel (and later listed as NGC 3548)
Historical Identification: Per Dreyer, NGC 3540 (= GC 2313 = JH 824, 1860 RA 11 01 32, NPD 53 12.7) is "very faint, round, pretty suddenly brighter middle, 7th magnitude star 7 arcmin to west".
Physical Information:

NGC 3541
Discovered (Feb 7, 1878) by
Wilhelm Tempel
Also observed (1880) by Andrew Common
Historical Identification: Per Dreyer, NGC 3541 (Common, (Tempel list I #31), 1860 RA 11 01 41, NPD 100 00) is a "nebulous star".
Discovery Notes: Dreyer apparently did not know about Tempel's prior observation, so it is included in the NGC entry in parentheses.
Physical Information:

NGC 3542
Discovered (Mar 26, 1884) by
Édouard Stephan
Historical Identification: Per Dreyer, NGC 3542 (Stephan list XIII (#60), 1860 RA 11 02 13, NPD 52 17.7) is "very faint, small, irregularly round, a little brighter middle, mottled but not resolved".
Physical Information:

NGC 3543
Discovered (Apr 9, 1793) by
William Herschel
Also observed (date?) by John Herschel
Historical Identification: Per Dreyer, NGC 3543 (= GC 2314 = JH 826 = WH III 920, 1860 RA 11 02 29, NPD 27 54.0) is "extremely faint, very small, extended 0°±, mottled but not resolved".
Physical Information:

NGC 3544 (=
NGC 3571)
Discovered (Mar 8, 1790) by William Herschel (and later listed as NGC 3571)
Discovered (Jan 7, 1886) by Ormond Stone (and later listed as NGC 3544)
Historical Identification: Per Dreyer, NGC 3544 (Ormond Stone list I (#184), 1860 RA 11 02 30, NPD 107 31.3) is "very faint, large, much extended 95°, brighter middle, equal to (WH) II 819?", II 819 being NGC 3571, so Stone's suspicion about the duplicate entry (stated in his notes as "G.C. 2330?") proved correct.
Discovery Notes: Despite Stone's (and Dreyer's) suspicion that his "nova" was a duplicate of Herschel's prior discovery, the fact that current usage generally assigns the lower NGC number to objects means that this object is almost always referred to as NGC 3544.
Physical Information:

NGC 3545
Discovered (Mar 26, 1884) by
Édouard Stephan
Historical Identification: Per Dreyer, NGC 3545 (Stephan list XIII (#61), 1860 RA 11 02 30, NPD 52 16.1) is "very faint, very small, irregularly round, a little brighter middle, mottled but not resolved".
Physical Information:

NGC 3546
Discovered (1886) by
Frank Muller
Also observed (date?) by Ormond Stone
Also observed (date?) by Herbert Howe
Historical Identification: Per Dreyer, NGC 3546 (Muller list II (#432), 1860 RA 11 02 30, NPD 102 38.3) is a "nebulous 12th magnitude star, with another 12th magnitude star 2 arcmin to the northeast".
The second IC lists a corrected RA (per Ormond Stone and Howe) of 11 02 47.
Physical Information:

NGC 3547
Discovered (Mar 11, 1784) by
William Herschel
Also observed (date?) by John Herschel
Historical Identification: Per Dreyer, NGC 3547 (= GC 2315 = JH 828 = WH II 42, 1860 RA 11 02 39, NPD 78 31.0) is "faint, small, a little extended, very little brighter middle".
Physical Information:

NGC 3548 (=
NGC 3540)
Discovered (Mar 11, 1831) by John Herschel (and later listed as NGC 3540)
Discovered (Feb 7, 1832) by John Herschel (and later listed as NGC 3548)
Historical Identification: Per Dreyer, NGC 3548 (= GC 2316 = JH 827, 1860 RA 11 02 41, NPD 53 12.6) is "extremely faint, small, 8th magnitude star to west".
Physical Information:

NGC 3549
Discovered (Apr 12, 1789) by
William Herschel
Historical Identification: Per Dreyer, NGC 3549 (= GC 2317 = WH I 220, 1860 RA 11 02 45, NPD 35 51.8) is "considerably bright, considerably large, considerably extended 160°".
Physical Information:
Celestial Atlas
(NGC 3450 - 3499) ←     NGC Objects: NGC 3500 - 3549     → (NGC 3550 - 3599)