Celestial Atlas
(NGC 500 - 549) ←     NGC Objects: NGC 550 - 599 Link for sharing this page on Facebook     → (NGC 600 - 649)
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Page last updated Apr 16, 2016
Checked Corwin positions, original NGC entries
WORKING: Update Steinicke data, pix, tags

NGC 550 (= PGC 5374)
Discovered (Oct 8, 1785) by
William Herschel
A magnitude 12.7 spiral galaxy (type SB(s)a?) in Cetus (RA 01 26 42.6, Dec +02 01 20)
Historical Identification: Per Dreyer, NGC 550 (= GC 326 = JH 122 = WH II 463, 1860 RA 01 19 31, NPD 88 42.5) is "faint, small, extended 90°, brighter middle, mottled but not resolved".
Physical Information: Apparent size 1.4 by 0.6 arcmin?
SDSS image of region near spiral galaxy NGC 550
Above, a 12 arcmin wide SDSS image centered on NGC 550
Below, a 2.4 arcmin wide SDSS image of the galaxy
SDSS image of spiral galaxy NGC 550

NGC 551 (= PGC 5450)
Discovered (Sep 21, 1786) by
William Herschel
A magnitude 12.7 spiral galaxy (type SBbc?) in Andromeda (RA 01 27 40.7, Dec +37 10 59)
Historical Identification: Per Dreyer, NGC 551 (= GC 327 = JH 123 = WH III 560, 1860 RA 01 19 43, NPD 53 32.5) is "very faint, small, extended, very gradually a little brighter middle, 13th magnitude star near".
Physical Information: Apparent size 1.8 by 0.8 arcmin?
SDSS image of region near spiral galaxy NGC 551 overlaid on a DSS background to fill in missing areas
Above, a SDSS image overlaid on a 12 arcmin wide DSS image centered on NGC 551
Below, a 2.4 arcmin wide SDSS image of the galaxy
SDSS image of spiral galaxy NGC 551

NGC 552
Recorded (Sep 13, 1784) by
William Herschel
A magnitude 14.6 star in Pisces (RA 01 26 10.0, Dec +33 24 21)
Historical Identification: Per Dreyer, NGC 552 (= GC 328 = WH III 172, 1860 RA 01 19 56, NPD 57 16.1) is "very small, stellar, the preceding (western) of 2, questionable RA", the other being NGC 553. There must have been something wrong with the way that Herschel's clock was running on the evening in question, as most of the objects he observed that night are nowhere near his reduced right ascensions. Corwin's analysis (to be covered in the next iteration of this page) suggests that NGC 552 is the star listed above; but the identification, though reasonable, cannot be considered certain. (Corwin also suggests a magnitude 14.3 star at RA 01 26 56.9, Dec +33 33 28)
Image of region near NGC 552 to be posted after completing a better analysis of the situation

NGC 553 (= PGC 5333)
Discovered (Sep 13, 1784) by
William Herschel
A 14th-magnitude lenticular galaxy (type S0) in Pisces (RA 01 26 12.5, Dec +33 24 19)
Historical Identification: Per Dreyer, NGC 553 (= GC 329 = WH III 173, 1860 RA 01 19 56, NPD 57 16.1) is "very small, stellar, the following (eastern) of 2, questionable RA", the other being NGC 552. There must have been something wrong with the way that Herschel's clock was running on the evening in question, as most of the objects he observed that night are nowhere near his reduced right ascensions. Corwin's analysis (to be covered in the next iteration of this page) suggests that NGC 553 is the galaxy listed above; but the identification, though reasonable, cannot be considered certain. (In fact Steinicke lists NGC 553 (and Corwin accepts as an unlikely possibility) a magnitude 14.8 pair of stars at RA 01 27 02.6, Dec +33 32 54).
Physical Information: Apparent size 0.6 by 0.3 arcmin?
Image of region near NGC 553 to be posted after completing a better analysis of the situation

NGC 554 (= PGC 5412 + PGC 5413)
Discovered (1886) by
Frank Muller
Also observed (date?) by Herbert Howe
A pair of galaxies in Cetus
PGC 5412 = A 14th-magnitude lenticular galaxy (type S0) at RA 01 27 09.6, Dec -22 43 34
PGC 5413 = A 14th-magnitude lenticular galaxy (type SB0) at RA 01 27 09.7, Dec -22 43 26
Historical Identification: Per Dreyer, NGC 554 (Muller list II (#305), 1860 RA 01 20 04, NPD 113 27.4) is "extremely faint, very small, extended, the 1st of 3 (the others being NGC 555 and NGC 556), 11th magnitude star to east". The second Index Catalog lists a corrected RA (per Howe) of 01 20 28. The object is a pair of galaxies too close to each other to have been in any way distinguishable from each other even with much better equipment than available in the 1800's.
Physical Information: Apparent size for PGC 5412 is 0.9 by 0.5 arcmin; for PGC 5413 it is 0.3 by 0.3 arcmin.
DSS image of the pair of lenticular galaxies listed as NGC 554, showing a faint extension probably due to a physical interaction; also shown are NGC 555 and NGC 556
Above, a 12 arcmin wide DSS image centered on NGC 554, also showing NGC 555 and 556
Below, a 1.2 arcmin wide DSS image of the galaxy pair
DSS image of the pair of lenticular galaxies listed as NGC 554, showing a faint extension probably due to a physical interaction

NGC 555 (= PGC 5419)
Discovered (1886) by
Frank Muller
Also observed (date?) by Herbert Howe
A 14th-magnitude lenticular galaxy (type SB0/a) in Cetus (RA 01 27 11.8, Dec -22 45 43)
Historical Identification: Per Dreyer, NGC 555 (Muller list II (#306), 1860 RA 01 20 04, NPD 113 29.4) is "extremely faint, small, irregularly round, 2nd of 3", the others being NGC 554 and 556. The second Index Catalog lists a corrected RA (per Howe) of 01 20 30.
Physical Information: Apparent size 0.7 by 0.6 arcmin?
DSS image of region near lenticular galaxy NGC 555, also showing NGC 554 and NGC 556
Above, a 12 arcmin wide DSS image centered on NGC 555, also showing NGC 554 and 556
Below, a 1.2 arcmin wide DSS image of the galaxy
DSS image of lenticular galaxy NGC 555

NGC 556 (= PGC 5420)
Discovered (1886) by
Frank Muller
Also observed (date?) by Herbert Howe
A 15th-magnitude lenticular galaxy (type E/S0?) in Cetus (RA 01 27 12.6, Dec -22 41 52)
Historical Identification: Per Dreyer, NGC 556 (Muller list II (#307), 1860 RA 01 20 04, NPD 113 25.4) is "extremely faint, very small, round, 3rd of 3", the others being NGC 554 and 555. The second Index Catalog lists a corrected RA (per Howe) of 01 20 31.
Physical Information: Apparent size 0.4 by 0.3 arcmin?
DSS image of region near lenticular galaxy NGC 556, also showing NGC 554 and NGC 555
Above, a 12 arcmin wide DSS image centered on NGC 556, also showing NGC 554 and 555
Below, a 1.2 arcmin wide DSS image of the galaxy
DSS image of lenticular galaxy NGC 556

NGC 557 (=
IC 1703 = PGC 5351)
Discovered (Nov 20, 1886) by Lewis Swift (and later listed as NGC 557)
Discovered (Oct 27, 1897) by Guillaume Bigourdan (and later listed as IC 1703)
A 14th-magnitude lenticular galaxy (type SB0/a??) in Cetus (RA 01 26 25.1, Dec -01 38 19)
Historical Identification: Per Dreyer, NGC 557 (Swift list VI (#11), 1860 RA 01 20 04, NPD 92 21.9) is "extremely faint, small, round, 10th magnitude star to northeast".
Physical Information: Apparent size 1.8 by 0.6 arcmin?
SDSS image of region near lenticular galaxy NGC 557
Above, a 12 arcmin wide SDSS image centered on NGC 557
Below, a 2 arcmin wide SDSS image of the galaxy
SDSS image of lenticular galaxy NGC 557

NGC 558 (= PGC 5425)
Discovered (Feb 1, 1864) by
Heinrich d'Arrest
A 14th-magnitude elliptical galaxy (type E5+?) in Cetus (RA 01 27 16.2, Dec -01 58 15)
Historical Identification: Per Dreyer, NGC 558 (= GC 5180, d'Arrest, 1860 RA 01 20 07, NPD 92 41.9), is "extremely faint, small, extended, 10th-magnitude star to west". The position precesses to within 0.4 arcmin of the correct position, and there is a star just off to the west (although only 11.5 magnitude), so the identification is certain.
Physical Information: Listed as part of Abell 194. Based on a recessional velocity of 4955 km/sec, NGC 558 is about 230 million light years away. Given that and its apparent size of 0.4 by 0.2 arcmin, it is about 25 thousand light years across. The galaxy seems to be universally classified as an elliptical, but its very elongated shape is more like that of a lenticular galaxy, so E/S0 might be a more accurate classification, and is the reason for listing it as E5+? instead of merely E5.
SDSS image of region near elliptical galaxy NGC 558, also showing NGC 560
Above, a 12 arcmin wide SDSS image centered on NGC 557, also showing NGC 560
Below, a 2.4 arcmin wide SDSS image of the galaxy
SDSS image of elliptical galaxy NGC 558

NGC 559 (= OCL 322)
Discovered (Nov 9, 1787) by
William Herschel
Also observed (Oct 5, 1829) by John Herschel
A 10th-magnitude open cluster (type II2m) in Cassiopeia (RA 01 29 32.0, Dec +63 18 06)
Historical Identification: Per Dreyer, NGC 559 (= GC 330 = JH 124 = WH VII 48, 1860 RA 01 20 10, NPD 27 25.9) is "a cluster, bright, pretty large, pretty rich".
Physical Information: Apparent size 7.0 arcmin?
DSS image of region near open cluster NGC 559
Above, a 12 arcmin wide DSS image centered on NGC 559

NGC 560 (= PGC 5430 =
IC 117)
Discovered (Oct 1, 1785) by William Herschel (and later listed as NGC 560)
Also observed (date?) by Heinrich d'Arrest (and later listed as NGC 560)
Also observed (Nov 21, 1876) by Édouard Stephan (and later listed as NGC 560)
Recorded (Nov 6, 1891) by Stephane Javelle (and later listed as IC 117)
A 13th-magnitude lenticular galaxy (type S0?) in Cetus (RA 01 27 25.4, Dec -01 54 47)
Historical Identification: Per Dreyer, NGC 560 (= GC 332 = WH III 441, d'Arrest, Stephan list VIII (#??), 1860 RA 01 20 19, NPD 92 38.8), is "very faint, very small, irregularly extended, western of 2", the other being NGC 564. The position precesses to within 0.5 arcmin of the galaxy listed above, so the identification is certain (and would be nailed down by the relative positions of NGC 560 and 564 even if the position were slightly in error).
Physical Information: Listed as part of Abell 194. Based on a recessional velocity of 5510 km/sec, NGC 560 is about 255 million light years away. Given that and its apparent size of 2.0 by 0.5 arcmin, it is about 150 thousand light years across.
SDSS image of region near lenticular galaxy NGC 560, also showing NGC 558 and NGC 564
Below, a 12 arcmin wide SDSS image centered on NGC 560, also showing NGC 558 and 564
Above, a 2.4 arcmin wide SDSS image of the galaxy
SDSS image of lenticular galaxy NGC 560

NGC 561 (= PC 5489)
Discovered (Aug 23, 1862) by
Heinrich d'Arrest
A 13th-magnitude spiral galaxy (type (R)SB(s)a?) in Andromeda (RA 01 28 18.8, Dec +34 18 31)
Historical Identification: Per Dreyer, NGC 561 (= GC 331, d'Arrest, 1860 RA 01 20 21, NPD 56 25.3) is "extremely faint, pretty large, round".
Physical Information: Apparent size 1.6 by 1.5 arcmin?
SDSS image of region near spiral galaxy NGC 561
Above, a 12 arcmin wide SDSS image centered on NGC 561
Below, a 2.4 arcmin wide SDSS image of the galaxy
SDSS image of spiral galaxy NGC 561

NGC 562 (= PGC 5502)
Discovered (Nov 30, 1885) by
Lewis Swift
A 13th-magnitude spiral galaxy (type SA(rs)c?) in Andromeda (RA 01 28 29.3, Dec +48 23 14)
Historical Identification: Per Dreyer, NGC 562 (Swift list III (#5), 1860 RA 01 20 21, NPD 42 20.3) is "extremely faint, pretty small, round, double star near to south".
Physical Information: Apparent size 1.3 by 1.1 arcmin?
SDSS image of region near spiral galaxy NGC 562
Above, a 12 arcmin wide SDSS image centered on NGC 562
Below, a 2.4 arcmin wide SDSS image of the galaxy
SDSS image of spiral galaxy NGC 562

NGC 563 (=
NGC 539 = PGC 5269)
Discovered (Oct 31, 1885) by Francis Leavenworth (and later listed as NGC 539)
Discovered (1886) by Francis Leavenworth (and later listed as NGC 563)
A 14th-magnitude spiral galaxy (type SB(rs)c?) in Cetus (RA 01 25 21.7, Dec -18 09 50)
Historical Identification: Per Dreyer, NGC 563 (Leavenworth list I (#30), 1860 RA 01 20 30, NPD 108 55.4) is "very faint, pretty small, a little extended, brighter middle and nucleus, several faint stars near".
Physical Information: Given the duplicate entry, see NGC 539 for anything else.

NGC 564 (= PGC 5455)
Discovered (Oct 1, 1785) by
William Herschel
Also observed (date?) by Heinrich d'Arrest
Also observed (Nov 21, 1876) by Édouard Stephan
A 13th-magnitude elliptical galaxy (type E2?) in Cetus (RA 01 27 48.2, Dec -01 52 46)
Historical Identification: Per Dreyer, NGC 564 (= GC 333 = WH III 442, d'Arrest, Stephan list VIII (#??), 1860 RA 01 20 40, NPD 92 36.9) is "very faint, very small, irregular figure, eastern of 2", the other being NGC 560. The position precesses to within 0.5 arcmin of the correct position, so the identification is certain (and would be nailed down by the relative positions of NGC 560 and 564 even if the positions were slightly in error).
Physical Information: Listed as part of Abell 194. Based on a recessional velocity of 5835 km/sec, NGC 564 is about 270 million light years away, in relatively poor agreement with redshift-independent distance estimates of about 200 million light years. Given that and its apparent size of 1.4 by 1.2 arcmin, it is about 110 thousand light years across.
SDSS image of elliptical galaxy NGC 564, also showing NGC 560
Above, a 12 arcmin wide SDSS image centered on NGC 564, also showing NGC 560
Below, a 2.4 arcmin wide SDSS image of the galaxy
SDSS image of elliptical galaxy NGC 564

NGC 565 (= PGC 5481)
Discovered (Nov 2, 1867) by
George Searle
A 14th-magnitude spiral galaxy (type Sa?) in Cetus (RA 01 28 10.2, Dec -01 18 22)
Historical Identification: Per Dreyer, NGC 565 (Searle (26, HN 34), 1860 RA 01 21 01, NPD 92 02.0) is "small, extended (perhaps bi-nuclear?)".
Physical Information: Apparent size 1.3 by 0.4 arcmin?
SDSS image of region near spiral galaxy NGC 565
Above, a 12 arcmin wide SDSS image centered on NGC 565
Below, a 2.4 arcmin wide SDSS image of the galaxy
SDSS image of spiral galaxy NGC 565

NGC 566 (= PGC 5545)
Discovered (Nov 22, 1827) by
John Herschel
A 14th-magnitude lenticular galaxy (type S0?) in Pisces (RA 01 29 03.0, Dec +32 19 56)
Historical Identification: Per Dreyer, NGC 566 (= GC 334 = JH 125, 1860 RA 01 21 11, NPD 58 23.8) is "very faint, small, round".
Physical Information: Apparent size 1.6 by 0.4 arcmin?
SDSS image of region near lenticular galaxy NGC 566
Above, a 12 arcmin wide SDSS image centered on NGC 566
Below, a 2 arcmin wide SDSS image of the galaxy
SDSS image of lenticular galaxy NGC 566

NGC 567 (= PGC 5402)
Discovered (1886) by
Francis Leavenworth
A 14th-magnitude lenticular galaxy (type S0?) in Cetus (RA 01 27 02.4, Dec -10 15 55)
Historical Identification: Per Dreyer, NGC 567 (Leavenworth list I (#31), 1860 RA 01 21 00, NPD 101 00.4) is "extremely faint, very small, round".
Physical Information: Apparent size 1.0 by 0.6 arcmin?
SDSS image of region near lenticular galaxy NGC 567
Above, a 12 arcmin wide SDSS image centered on NGC 567
Below, a 2 arcmin wide SDSS image of the galaxy
SDSS image of lenticular galaxy NGC 567

NGC 568 (=
IC 1709 = PGC 5468)
Discovered (Nov 29, 1837) by John Herschel (and later listed as NGC 568)
Discovered (Sep 4, 1897) by Lewis Swift (and later listed as IC 1709)
A 13th-magnitude lenticular galaxy (type E/S0?) in Sculptor (RA 01 27 57.0, Dec -35 43 03)
Historical Identification: Per Dreyer, NGC 568 (= GC 335 = JH 2414, 1860 RA 01 21 37, NPD 126 27.0) is "very faint, small, round".
Physical Information: Apparent size 2.2 by 1.3 arcmin?
DSS image of region near lenticular galaxy NGC 568
Above, a 12 arcmin wide DSS image centered on NGC 568
Below, a 3 arcmin wide DSS image of the galaxy
DSS image of lenticular galaxy NGC 568

NGC 569 (= PGC 5548)
Discovered (Oct 1, 1864) by
Albert Marth (#49)
A 14th-magnitude spiral galaxy (type Sbc) in Pisces (RA 01 29 07.2, Dec +11 07 53)
Historical Identification: Per Dreyer, NGC 569 (= GC 5181, Marth #49, 1860 RA 01 21 44, NPD 79 35) is "extremely faint, very small, round".
Physical Information: Apparent size 1.0 by 0.45 arcmin (from images below). Recessional velocity 5795 km/sec. A probable companion of PGC 5555.
SDSS image of region near spiral galaxy NGC 569, also showing PGC 5555
Above, a 12 arcmin wide SDSS image centered on NGC 569, also showing PGC 5555
Below, a 2.4 arcmin wide SDSS image of the galaxy and its probable companion
SDSS image of spiral galaxy NGC 569 and PGC 5555
Below, a 1.25 arcmin wide SDSS image of the galaxy
SDSS image of spiral galaxy NGC 569

PGC 5555
Not an NGC object but listed here because a probable companion of
NGC 569
A 15th-magnitude spiral galaxy (type SAB(s)bc?) in Pisces (RA 01 29 11.1, Dec +11 08 26)
Physical Information: Apparent size 1.2 by 0.5 arcmin (from image below). Recessional velocity 5780 km/sec. A probable companion of NGC 569.
SDSS image of spiral galaxy PGC 5555, a probable companion of NGC 569
Above, a 1.4 arcmin wide SDSS image of PGC 5555 (see NGC 569 for more images)

NGC 570 (= PGC 5539)
Discovered (Oct 31, 1867) by
George Searle
A 13th-magnitude spiral galaxy (type (R)SB(rs)a?) in Cetus (RA 01 28 58.6, Dec -00 56 56)
Historical Identification: Per Dreyer, NGC 570 (Searle (27, HN 32), 1860 RA 01 21 50, NPD 91 40.5) is "very faint, pretty large, round, much brighter middle and nucleus".
Physical Information: Apparent size 1.6 by 1.3 arcmin?
SDSS image of region near spiral galaxy NGC 570
Above, a 12 arcmin wide SDSS image centered on NGC 570
Below, a 2.4 arcmin wide SDSS image of the galaxy
SDSS image of spiral galaxy NGC 570

NGC 571 (= PGC 5587)
Discovered (Oct 1, 1864) by
Heinrich d'Arrest
A 14th-magnitude spiral galaxy (type Sbc??) in Pisces (RA 01 29 56.0, Dec +32 30 05)
Historical Identification: Per Dreyer, NGC 571 (= GC 5182, d'Arrest, 1860 RA 01 22 02, NPD 58 13.5) is "very faint, pretty small, 13th or 14th magnitude star to southwest".
Physical Information: Apparent size 1.3 by 1.3 arcmin?
SDSS image of region near spiral galaxy NGC 571
Above, a 12 arcmin wide SDSS image centered on NGC 571
Below, a 2.4 arcmin wide SDSS image of the galaxy
SDSS image of spiral galaxy NGC 571

NGC 572 (= PGC 5508)
Discovered (Sep 4, 1834) by
John Herschel
A 14th-magnitude lenticular galaxy (type SB0??) in Sculptor (RA 01 28 36.4, Dec -39 18 27)
Historical Identification: Per Dreyer, NGC 572 (= GC 336 = JH 2415, 1860 RA 01 22 21, NPD 130 02.4) is "extremely faint, small, attached to small (faint) star, bright star near".
Physical Information: Apparent size 0.8 by 0.8 arcmin (from image below)
DSS image of region near lenticular galaxy NGC 572
Above, a 12 arcmin wide DSS image centered on NGC 572
Below, a 1.2 arcmin wide DSS image of the galaxy
DSS image of lenticular galaxy NGC 572

NGC 573 (= PGC 5638)
Discovered (Oct 21, 1881) by
Édouard Stephan
A 13th-magnitude spiral galaxy (type S?) in Andromeda (RA 01 30 49.4, Dec +41 15 26)
Historical Identification: Per Dreyer, NGC 573 (Stephan list XII (#15), 1860 RA 01 22 40, NPD 49 28.0) is "very faint, very small, round, gradually brighter middle".
Physical Information: Apparent size 0.4 by 0.4 arcmin?
SDSS image of region near spiral galaxy NGC 573
Above, a 12 arcmin wide SDSS image centered on NGC 573
Below, a 2.4 arcmin wide SDSS image of the galaxy
SDSS image of spiral galaxy NGC 573

NGC 574 (= PGC 5544)
Discovered (Sep 1, 1834) by
John Herschel
A 13th-magnitude spiral galaxy (type (R)SB(rs)b?) in Sculptor (RA 01 29 03.1, Dec -35 35 56)
Historical Identification: Per Dreyer, NGC 574 (= GC 337 = JH 2416, 1860 RA 01 22 44, NPD 126 19.5) is "very small, double star involved at position angle 225°". (I see no evidence of a double star in the images below, but there are two bright patches within the extended nucleus which may have given that impression.)
Physical Information: Apparent size 1.1 by 0.7 arcmin?
DSS image of region near spiral galaxy NGC 574
Above, a 12 arcmin wide DSS image centered on NGC 574
Below, a 2.4 arcmin wide DSS image of the galaxy
DSS image of spiral galaxy NGC 574

NGC 575 (=
IC 1710 = PGC 5634)
Discovered (Oct 17, 1876) by Édouard Stephan= (and later listed as NGC 575)
Discovered (Jan 18, 1896) by Stephane Javelle (and later listed as IC 1710)
A 13th-magnitude spiral galaxy (type SB(rs)c?) in Pisces (RA 01 30 46.6, Dec +21 26 26)
Historical Identification: Per Dreyer, NGC 575 (= GC 5183, Stephan list VIII (#5), 1860 RA 01 23 10, NPD 67 17.0) is "extremely faint, pretty large, irregularly round".
Physical Information: Apparent size 1.7 by 1.6 arcmin?
SDSS image of region near spiral galaxy NGC 575
Above, a 12 arcmin wide SDSS image centered on NGC 575
Below, a 2.4 arcmin wide SDSS image of the galaxy
SDSS image of spiral galaxy NGC 575

NGC 576 (= PGC 5535)
Discovered (Oct 3, 1834) by
John Herschel
A 13th-magnitude lenticular galaxy (type SB0/a?) in Phoenix (RA 01 28 57.6, Dec -51 35 55)
Historical Identification: Per Dreyer, NGC 576 (= GC 338 = JH 2417, 1860 RA 01 23 15, NPD 142 18.9) is "faint, small, round, brighter middle, among 11th magnitude stars".
Physical Information: Apparent size 1.0 by 0.8 arcmin?
DSS image of region near lenticular galaxy NGC 576
Above, a 12 arcmin wide DSS image centered on NGC 576
Below, a 1.5 arcmin wide DSS image of the galaxy
DSS image of lenticular galaxy NGC 576

NGC 577 (=
NGC 580 = PGC 5628)
Discovered (Oct 23, 1867) by Aaron Skinner (and later listed as NGC 577)
Discovered (Aug 14, 1877) by Wilhelm Tempel (and later listed as NGC 577 and NGC 580)
Also observed (date?) by Lewis Swift (and later listed as NGC 580)
Also observed (date?) by Herbert Howe (while listed as NGC 580)
A 13th-magnitude spiral galaxy (type (R)SB(r)a? pec) in Cetus (RA 01 30 40.7, Dec -01 59 40)
Historical Identification: Per Dreyer, NGC 577 (= Tempel list I (#8), list II (#??), (Skinner #100), 1860 RA 01 23 34, NPD 92 43.1) is "faint". Skinner discovered the object in 1867, but his observation was not published until 1886, and even then only in a footnote to another paper, so Dreyer had little chance to note its existence prior to the publication of the NGC, and Tempel's "rediscovery" was an independent observation (although as will be noted in the discussion of the double listing at NGC 580, muddled by an apparently fatal error in another observation on the same night). In any event, the position precesses to exactly the correct position, so the current identification is certain.
Physical Information: Listed as possible member of Abell 194. Based on a recessional velocity of 5935 km/sec, NGC 577 is about 275 million light years away. Given that and its apparent size of 1.9 by 1.4 arcmin, it is about 150 thousand light years across.
SDSS image of region near spiral galaxy NGC 577
Above, a 12 arcmin wide SDSS image centered on NGC 577
Below, a 2.4 arcmin wide SDSS image of the galaxy
SDSS image of spiral galaxy NGC 577

NGC 578 (= PGC 5619)
Discovered (Nov 11, 1835) by
John Herschel
An 11th-magnitude spiral galaxy (type SAB(rs)c?) in Cetus (RA 01 30 28.6, Dec -22 40 02)
Historical Identification: Per Dreyer, NGC 578 (= GC 339 = JH 2418, 1860 RA 01 23 44, NPD 113 23.7) is "bright, large, pretty much extended, gradually pretty much brighter middle".
Physical Information: Apparent size 4.8 by 3.0 arcmin?
NOAO image of region near spiral galaxy NGC 578 superimposed on a DSS background to fill in missing areas
Above, a NOAO image overlaid on a 12 arcmin wide DSS image centered on NGC 578
Below, a 5 arcmin wide image of the galaxy (Credit above and below Adam Block/NOAO/AURA/NSF)
NOAO image of spiral galaxy NGC 578

NGC 579 (= PGC 5691)
Discovered (Nov 22, 1827) by
John Herschel
A 13th-magnitude spiral galaxy (type Scd?) in Triangulum (RA 01 31 46.5, Dec +33 36 56)
Historical Identification: Per Dreyer, NGC 579 (= GC 340 = JH 127, 1860 RA 01 23 51, NPD 57 06.2) is "very faint, pretty large, gradually brighter middle".
Physical Information: Apparent size 1.5 by 1.3 arcmin?
SDSS image of region near spiral galaxy NGC 579
Above, a 12 arcmin wide SDSS image centered on NGC 579
Below, a 2.4 arcmin wide SDSS image of the galaxy
SDSS image of spiral galaxy NGC 579

NGC 580 (=
NGC 577 = PGC 5628)
Discovered (Oct 23, 1867) by Aaron Skinner (and later listed as NGC 577)
Discovered (Aug 14, 1877) by Wilhelm Tempel (and later listed as NGC 577 and NGC 580)
Also observed (Nov 20, 1886) by Lewis Swift (and later listed as NGC 580)
Also observed (date?) by Herbert Howe (while listed as NGC 580)
A 13th-magnitude spiral galaxy (type (R)SB(r)a? pec) in Cetus (RA 01 30 40.7, Dec -01 59 40)
Historical Identification: Per Dreyer, NGC 580 (Tempel list I (#8), Swift list VI (#??), 1860 RA 01 23 59, NPD 92 43.5) is "pretty faint, pretty small, round". The second Index Catalog lists a corrected RA (per Howe) of 01 23 34. A detailed discussion of the double listing to be added when time permits. For now, refer to Corwin.
Physical Information: Given the duplicate entry, see NGC 577 for anything else.

NGC 581 (= OCL 326 =
M103)
Discovered (April 1781) by Pierre Méchain
Recorded (date?) by Charles Messier as M103
Also observed (date?) by John Herschel
Also observed (1825) by Wilhelm Struve
A 7th-magnitude open cluster (type III2p) in Cassiopeia (RA 01 33 23.0, Dec +60 39 24)
Historical Identification: Per Dreyer, NGC 581 (= GC 341 = JH 126, M103, Struve 131, 1860 RA 01 24 00, NPD 30 01.5) is "a cluster, pretty large, bright, round, rich, stars from 10th to 11th magnitude".
Discovery Notes: Struve 131 is a double star near but not actually part of M103, but apparently Dreyer used Struve's notes about the double star and its surroundings, as he would otherwise not have mentioned that observation in the NGC entry.
Physical Information: Apparent size 6.0 arcmin?
NOAO image of open cluster NGC 581, also known as M103
Above, a ? arcmin wide image of NGC 581
(Image Credit Hillary Mathis & N. A. Sharp, KPNO 2.1-m Tel., AURA, NSF, NOAO)

NGC 582 (= PGC 5702)
Discovered (Aug 9, 1863) by
Heinrich d'Arrest
A 13th-magnitude spiral galaxy (type SBb??) in Triangulum (RA 01 31 58.1, Dec +33 28 36)
Historical Identification: Per Dreyer, NGC 582 (= GC 5184, d'Arrest, 1860 RA 01 24 04, NPD 57 14.4) is "very faint, pretty large, pretty much extended, 12th magnitude star to west".
Physical Information: Apparent size 2.2 by 0.6 arcmin?
SDSS image of region near spiral galaxy NGC 582
Above, a 12 arcmin wide SDSS image centered on NGC 582
Below, a 2.4 arcmin wide SDSS image of the galaxy
SDSS image of spiral galaxy NGC 582

NGC 583 (= PGC 5576)
Discovered (1886) by
Francis Leavenworth
Also observed (date?) by Herbert Howe
A 14th-magnitude lenticular galaxy (type SB0??) in Cetus (RA 01 29 44.2, Dec -18 20 22)
Historical Identification: Per Dreyer, NGC 583 (Leavenworth list II (#308), 1860 RA 01 24 09, NPD 109 04.4) is "extremely faint, small, round". The second Index Catalog lists a corrected RA (per Howe) of 01 22 57.
Physical Information: Apparent size 0.7 by 0.6 arcmin?
DSS image of region near lenticular galaxy NGC 583
Above, a 12 arcmin wide DSS image centered on NGC 583
Below, a 1.5 arcmin wide DSS image of the galaxy
DSS image of lenticular galaxy NGC 583

NGC 584 (=
IC 1712 = PGC 5663)
Discovered (Sep 10, 1785) by William Herschel (and later listed as NGC 584)
Also observed (date?) by John Herschel (and later listed as NGC 584)
Discovered (Nov 30, 1885) by Lewis Swift (and later listed as IC 1712)
Also observed (date?) by Herbert Howe (while listed as NGC 584)
An 11th-magnitude elliptical galaxy (type E4?? E/SA0??) in Cetus (RA 01 31 20.7, Dec -06 52 05)
Historical Identification: Per Dreyer, NGC 584 (= GC 342 = JH 128 = WH I 100, 1860 RA 01 24 20, NPD 97 35.4) is "very bright, pretty large, round, much brighter middle, western of 2", the other presumably being NGC 586. The second Index Catalog lists a corrected RA (per Howe) of 01 22 57.
Physical Information: Apparent size 4.1 by 2.0 arcmin? Used by the de Vaucouleurs Atlas of Galaxy Types as an example of galaxy type SA0-.
SDSS image of region near elliptical galaxy NGC 584, also showing NGC 586
Below, a 12 arcmin wide SDSS image centered on NGC 584, also showing NGC 586
Below, a 4 arcmin wide SDSS image of the galaxy
SDSS image of elliptical galaxy NGC 584

NGC 585 (= PGC 5688)
Discovered (Dec 20, 1827) by
John Herschel
A 13th-magnitude spiral galaxy (type Sa??) in Cetus (RA 01 31 42.1, Dec -00 55 59)
Historical Identification: Per Dreyer, NGC 585 (= GC 345 = JH 129, 1860 RA 01 24 27, NPD 91 38.5) is "very faint, small, round, brighter middle".
Physical Information: Apparent size 2.4 by 0.5 arcmin?
SDSS image of region near spiral galaxy NGC 585
Above, a 12 arcmin wide SDSS image centered on NGC 585
Below, a 2.4 arcmin wide SDSS image of the galaxy
SDSS image of spiral galaxy NGC 585

NGC 586 (= PGC 5679)
Discovered (Sep 10, 1785) by
William Herschel
Also observed (date?) by John Herschel
Also observed (Nov 29, 1856) by R. J. Mitchell
A 13th-magnitude spiral galaxy (type SA(s)a?) in Cetus (RA 01 31 36.9, Dec -06 53 38)
Historical Identification: Per Dreyer, NGC 586 (= GC 343 = GC 344 = GC 346 = JH 130 = WH III 431, 1860 RA 01 24 36, NPD 97 37.0) is "very faint, very small, round".
Physical Information: Apparent size 1.7 by 0.9 arcmin?
SDSS image of region near spiral galaxy NGC 586, also showing NGC 584
Above, a 12 arcmin wide SDSS image centered on NGC 586, also showing NGC 584
Below, a 2.4 arcmin wide SDSS image of the galaxy
SDSS image of spiral galaxy NGC 586

NGC 587 (= PGC 5746)
Discovered (Aug 27, 1862) by
Heinrich d'Arrest
A 13th-magnitude spiral galaxy (type SAB(s)b?) in Triangulum (RA 01 32 33.3, Dec +35 21 31)
Historical Identification: Per Dreyer, NGC 587 (= GC 347, d'Arrest, 1860 RA 01 24 41, NPD 55 26.3) is "very very faint, small, perhaps a small cluster".
Physical Information: Apparent size 2.2 by 0.8 arcmin?
DSS image of region near spiral galaxy NGC 587
Above, a 12 arcmin wide SDSS image centered on NGC 587
Below, a 2.4 arcmin wide SDSS image of the galaxy
DSS image of spiral galaxy NGC 587

NGC 588 (in the Triangulum Galaxy,
M33)
Discovered (Oct 2, 1861) by Heinrich d'Arrest
A 14th-magnitude star cluster and emission nebula in Triangulum (RA 01 32 45.5, Dec +30 38 56)
Historical Identification: Per Dreyer, NGC 588 (= GC 348, d'Arrest, 1860 RA 01 24 54, NPD 60 04.4) is "faint, western of 2", the other being NGC 592.
Physical Information: Apparent size 0.65 arcmin?
SDSS image of region near the star cluster and emission nebula listed as NGC588, in the Triangulum Galaxy, M33; also shown is NGC 592
Above, a 12 arcmin wide SDSS image centered on NGC 588, also showing NGC 592
Below, a 1.2 arcmin wide SDSS image of the cluster and emission nebula
SDSS image of the star cluster and emission nebula listed as NGC588, in the Triangulum Galaxy, M33
Below, a 42 by 45 arcmin DSS finding chart for NGC/IC objects in M33
(N### indicates an NGC object, ### an IC object)
Labeled DSS image showing NGC and IC objects in the spiral galaxy NGC 598, also known as the Triangulum Galaxy, M33

NGC 589 (= PGC 5758)
Discovered (1886) by
Frank Muller
Also observed (date?) by Herbert Howe
A 14th-magnitude lenticular galaxy (type (R)S0/a?) in Cetus (RA 01 32 39.9, Dec -12 02 34)
Historical Identification: Per Dreyer, NGC 589 (Muller list II (#309), 1860 RA 01 24 55, NPD 102 45.4) is "very faint, small, round, gradually brighter middle and nucleus, 10th magnitude star 2 arcmin to southwest". The second Index Catalog lists a corrected RA (per Howe) of 01 25 46.
Physical Information: Apparent size 1.1 by 0.9 arcmin?
DSS image of region near lenticular galaxy NGC 589
Above, a 12 arcmin wide DSS image centered on NGC 589
Below, a 1.5 arcmin wide DSS image of the galaxy
DSS image of lenticular galaxy NGC 589

NGC 590 (= PGC 5808)
Discovered (Sep 22, 1865) by
Heinrich d'Arrest
A 13th-magnitude lenticular galaxy (type SB0(s)a?) in Andromeda (RA 01 33 40.9, Dec +44 55 44)
Historical Identification: Per Dreyer, NGC 590 (= GC 5185, d'Arrest, 1860 RA 01 25 17, NPD 45 47.4) is "faint, very small, partially resolved? perhaps some stars seen?".
Physical Information: Apparent size 2.6 by 1.3 arcmin?
SDSS image of region near lenticular galaxy NGC 590
Above, a 12 arcmin wide SDSS image centered on NGC 590
Below, a 3 arcmin wide SDSS image of the galaxy
SDSS image of lenticular galaxy NGC 590

NGC 591 (= PGC 5800)
Discovered (Oct 10, 1866) by
Truman Safford
Also observed (Nov 30, 1885) by Lewis Swift
A 13th-magnitude lenticular galaxy (type (R)SB0(s)a?) in Andromeda (RA 01 33 31.2, Dec +35 40 06)
Historical Identification: Per Dreyer, NGC 591 (Swift list III (#??), (Safford 61), 1860 RA 01 25 18, NPD 55 03.7) is "extremely faint, pretty small, round, a little brighter middle, bright star to southeast".
Discovery Notes: Safford's observations, although made 20-some years beforehand, were not published until the late 1880's, and even then only in an obscure journal, so Dreyer was not aware of their existence until the NGC was nearly ready to go to press. As a result, he did not have the opportunity to list Safford's observations in the main part of the text, and only noted a few of them in an appendix at the end of the paper.
Physical Information: Apparent size 1.3 by 1.0 arcmin?
DSS image of region near lenticular galaxy NGC 591
Above, a 12 arcmin wide DSS image centered on NGC 591
Below, a 1.5 arcmin wide DSS image of the galaxy
DSS image of lenticular galaxy NGC 591

NGC 592 (in the Triangulum Galaxy,
M33)
Discovered (Oct 2, 1861) by Heinrich d'Arrest
A 13th-magnitude star cluster and emission nebula in Triangulum (RA 01 33 12.2, Dec +30 38 44)
Historical Identification: Per Dreyer, NGC 592 (= GC 349, d'Arrest, 1860 RA 01 25 21, NPD 60 04.6) is "faint, pretty large, eastern of 2", the other being NGC 588.
Physical Information: Apparent size 0.70 arcmin?
SDSS image of region near the star cluster and emission nebula listed as NGC 592, in the Triangulum Galaxy, M33; also shown are NGC 588, NGC 595, and IC 131
Above, a 12 arcmin wide SDSS image centered on NGC 592, also showing NGC 588 and 595, and IC 131
Below, a 1.2 arcmin wide SDSS image of the cluster and nebula
SDSS image of the star cluster and emission nebula listed as NGC 592, in the Triangulum Galaxy, M33
Below, a 42 by 45 arcmin DSS finding chart for NGC/IC objects in M33
(N### indicates an NGC object, ### an IC object)
Labeled DSS image showing NGC and IC objects in the spiral galaxy NGC 598, also known as the Triangulum Galaxy, M33

NGC 593 (= PGC 5733 = PGC 954102)
Discovered (Nov 2, 1882) by
Édouard Stephan
A 15th-magnitude lenticular galaxy (type SB0?) in Cetus (RA 01 32 20.8, Dec -12 21 16)
Historical Identification: Per Dreyer, NGC 593 (Stephan list XII (#17), 1860 RA 01 25 27, NPD 103 04.7) is "a very small cluster, a little extended, nebulous". (A Wikisky search for NGC 593 shows the correct object, but labeled as PGC 954102.)
Physical Information: Apparent size 1.2 by 0.2 arcmin?
DSS image of region near lenticular galaxy NGC 593
Above, a 12 arcmin wide DSS image centered on NGC 593
Below, a 1.5 arcmin wide DSS image of the galaxy
DSS image of lenticular galaxy NGC 593

NGC 594 (= PGC 5769 =
IC 1714???)
Discovered (1886) by Francis Leavenworth
A 14th-magnitude spiral galaxy (type Sbc?) in Cetus (RA 01 32 56.9, Dec -16 32 09)
Historical Identification: Per Dreyer, NGC 594 (Leavenworth list I (#32), 1860 RA 01 25 30, NPD 107 16.3) is "faint, pretty small, extended, gradually a little brighter middle".
Physical Information: Apparent size 1.4 by 0.6 arcmin?
DSS image of region near spiral galaxy NGC 594
Above, a 12 arcmin wide DSS image centered on NGC 594
Below, a 2.4 arcmin wide DSS image of the galaxy
DSS image of spiral galaxy NGC 594

NGC 595 (in the Triangulum Galaxy,
M33)
Discovered (Oct 1, 1864) by Heinrich d'Arrest
Also observed (Nov 1, 1866) by Truman Safford
A 15th-magnitude emission nebula in Triangulum (RA 01 33 33.8, Dec +30 41 31)
Historical Identification: Per Dreyer, NGC 595 (= GC 5186, d'Arrest, (Safford #??), 1860 RA 01 25 42, NPD 60 01.7) is "very faint, small, round, involved in M33".
Discovery Notes: Safford's observations, although made 20-some years beforehand, were not published until the late 1880's, and even then only in an obscure journal, so Dreyer was not aware of their existence until the NGC was nearly ready to go to press. As a result, he did not have the opportunity to list Safford's observations in the main part of the text, and only noted a few of them in an appendix at the end of the paper.
Physical Information: Apparent size 0.50 arcmin?
SDSS image of region near emission nebula NGC 595, also showing NGC 592, IC 131 and IC 142
Above, a 12 arcmin wide SDSS image centered on NGC 595, also showing NGC 592, IC 131 and 142
Below, a 1.8 by 2.0 arcmin wide SDSS image of the nebula
SDSS image of emission nebula NGC 595
Below, a 42 by 45 arcmin DSS finding chart for NGC/IC objects in M33
(N### indicates an NGC object, ### an IC object)
Labeled DSS image showing NGC and IC objects in the spiral galaxy NGC 598, also known as the Triangulum Galaxy, M33

NGC 596 (= PGC 5766)
Discovered (Dec 13, 1783) by
William Herschel
Also observed (date?) by John Herschel
An 11th-magnitude elliptical galaxy (type E4?) in Cetus (RA 01 32 51.9, Dec -07 01 54)
Historical Identification: Per Dreyer, NGC 596 (= GC 351 = JH 132 = WH II 4, 1860 RA 01 25 51, NPD 97 45.1) is "pretty bright, round, brighter middle, mottled but not resolved, 6th magnitude star 12 arcmin to east".
Physical Information: Apparent size 3.2 by 2.0 arcmin?
SDSS image of region near elliptical galaxy NGC 596
Above, a 12 arcmin wide SDSS image centered on NGC 596
Below, a 4 arcmin wide SDSS image of the galaxy
SDSS image of elliptical galaxy NGC 596

NGC 597 (= PGC 5721)
Discovered (Sep 25, 1834) by
John Herschel
A 13th-magnitude spiral galaxy (type SB(s)bc?) in Sculptor (RA 01 32 14.9, Dec -33 29 50)
Historical Identification: Per Dreyer, NGC 597 (= GC 350 = JH 2419, 1860 RA 01 25 53, NPD 124 13.5) is "faint, small, round, brighter middle".
Physical Information: Apparent size 1.4 by 1.3 arcmin?
DSS image of region near spiral galaxy NGC 597
Above, a 12 arcmin wide DSS image centered on NGC 597
Below, a 2.4 arcmin wide DSS image of the galaxy
DSS image of spiral galaxy NGC 597

WORKING HERE: Need to add better images

NGC 598 (= PGC 5818 =
M33), the Triangulum Galaxy
Discovered (before 1654) by Giovanni Hodierna
Recorded (Aug 25, 1764) by Charles Messier as M33
Also observed (Aug 18, 1775) by Johann Bode
Also observed (Sep 11, 1784) by William Herschel
Also observed (Sep 15, 1828) by John Herschel
A magnitude 5.7 spiral galaxy (type SA(s)cd?) in Triangulum (RA 01 33 50.9, Dec +30 39 37)
Historical Identification: Per Dreyer, NGC 598 (= GC 352 = JH 131 = WH V 17, M 33, 1860 RA 01 25 58, NPD 60 03.8) is "a remarkable object, extremely bright, extremely large, round, very gradually much brighter middle and nucleus". The position precesses to RA 01 33 50.1, Dec +30 39 25, right on the nucleus of the galaxy, so the identification is certain. (Note: See the discussion of Hodierna for an explanation of why he was not credited with the discovery of any NGC object.)
Physical Information: M33 is a member of the Local Group of Galaxies, and as such its recessional velocity of -180 km/sec represents its random motion relative to our galaxy, and has nothing to do with the Universal expansion; so it cannot be used to estimate the distance of the galaxy. However, dozens of redshift-independent distance estimates indicate that the galaxy is between 2 and 4 million light years away. Given that and its apparent size of 60 by 35 arcmin, it is about 50 thousand light years across.
NOAO image of spiral galaxy NGC 598, also known as the Triangulum Galaxy, M33
Above, a ? arcmin wide image of NGC 598 (Image credit Adam Block/AURA/NSF/NOAO)
Below, a ? arcmin wide image of the central fifth of the galaxy (Image credit as above)
NOAO closeup of central fifth of spiral galaxy NGC 598, also known as the Triangulum Galaxy, M33
Below, a DSS image of the galaxy showing a region about one degree high and 45 arcmin wide
DSS image of spiral galaxy NGC 598, also known as the Triangulum Galaxy, M33
Below, a 42 by 45 arcmin DSS finding chart for NGC/IC objects in M33
(N### indicates an NGC object, ### an IC object)
Labeled DSS image showing NGC and IC objects in the spiral galaxy NGC 598, also known as the Triangulum Galaxy, M33

NGC 599 (= PGC 5778)
Discovered (Nov 27, 1785) by
William Herschel
Also observed (1886) by Frank Muller
A 13th-magnitude lenticular galaxy (type E/S0?) in Cetus (RA 01 32 53.8, Dec -12 11 29)
Historical Identification: Per Dreyer, NGC 599 (= GC 353 = WH II 473, Muller list II (#??), 1860 RA 01 26 01, NPD 102 53.3) is "faint, small, irregular figure, extremely mottled but not resolved".
Physical Information: Apparent size 1.4 by 1.3 arcmin?
DSS image of region near spiral galaxy NGC 599, also showing NGC 601
Above, a 12 arcmin wide DSS image centered on NGC 599, also showing NGC 601
Below, a 2.4 arcmin wide DSS image of the galaxy
DSS image of spiral galaxy NGC 599
Celestial Atlas
(NGC 500 - 549) ←     NGC Objects: NGC 550 - 599     → (NGC 600 - 649)