Celestial Atlas
(NGC 4500 - 4549) ←NGC Objects: NGC 4550 - 4599→ (NGC 4600 - 4649)
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Page last updated Aug 13, 2022
Updated and completed entries & images for NGC 4567/8, The Siamese Twins
Checked all positions
WORKING 4556: Checking magnitudes, designations

NGC 4550
(= PGC 41943 = UGC 7757 = CGCG 70-182 = MCG +02-32-147)

Discovered (Apr 17, 1784) by
William Herschel
A magnitude 11.7 lenticular galaxy (type SB0°?) in Virgo (RA 12 35 30.6, Dec +12 13 15)
Apparent size 3.5 by 1.0 arcmin. Listed as a member (VCC 1619) of the Virgo Cluster.
SDSS image of region near lenticular galaxy NGC 4550, also showing NGC 4551
Above, a 12 arcmin wide SDSS image centered on NGC 4550, also showing NGC 4551
Below, a 3.6 arcmin wide SDSS image of the galaxy
SDSS image of lenticular galaxy NGC 4550

NGC 4551
(= PGC 41963 = UGC 7759 = CGCG 70-183 = MCG +02-32-148)

Discovered (Apr 17, 1784) by
William Herschel
A magnitude 12.0 elliptical galaxy (type E3?) in Virgo (RA 12 35 38.0, Dec +12 15 50)
Apparent size 2.2 by 1.6 arcmin. Listed as a member (VCC 1630) of the Virgo Cluster.
SDSS image of region near elliptical galaxy NGC 4551, also showing NGC 4550
Above, a 12 arcmin wide SDSS image centered on NGC 4551, also showing NGC 4550
Below, a 2.4 arcmin wide SDSS image of the galaxy
SDSS image of elliptical galaxy NGC 4551

NGC 4552 (=
M89)
(= PGC 41968 = UGC 7760 = CGCG 070-184 = MCG +02-32-149)

Discovered (Mar 18, 1781) by Charles Messier and recorded as M89
Also observed (Apr 10, 1825) by John Herschel
A magnitude 9.8 elliptical galaxy (type (R')E1? pec) in Virgo (RA 12 35 39.8, Dec +12 33 23)
Historical Identification: Per Dreyer, NGC 4552 (= GC 3097 = JH 1348, M89, 1860 RA 12 28 36, NPD 76 40.3) is "pretty bright, pretty small, round, gradually much brighter middle". The position precesss to RA 12 35 40.3, Dec +12 33 23, essentially dead center on the galaxy listed above and the description fits, so the identification is certain.
Physcial Information: Apparent size 3.8 by 3.3 arcmin; fainter outer regions cover about 8.8 by 7.2 arcmin. Listed as a member (VCC 1632) of the Virgo Cluster.
SDSS image of region near elliptical galaxy NGC 4552, also known as M89
Above, a 12 arcmin wide SDSS image centered on NGC 4552
Below, the image above enhanced to better show fainter outer regions of the galaxy
SDSS image of region near elliptical galaxy NGC 4552, also known as M89, enhanced to show fainter outer regions
Below, a 4 arcmin wide SDSS image of the galaxy
SDSS image of elliptical galaxy NGC 4552, also known as M89

NGC 4553
(= PGC 42018 = ESO 322-030 = MCG -06-28-06)

Discovered (Apr 22, 1835) by
John Herschel
A magnitude 12.2 lenticular galaxy (type SA(r)0+) in Centaurus (RA 12 36 07.6, Dec -39 26 19)
Apparent size 2.4 by 1.5 arcmin. (Need size of brighter inner region, and fainter outer outline, from images below)
Use By The deVaucouleurs Atlas: NGC 4553 is used by The deVaucouleurs Atlas of Galaxies as an example of type SA(r)0+ (whence the type shown above).
DSS image of region near lenticular galaxy NGC 4553
Above, a 12 arcmin wide DSS image centered on NGC 4553
Below, a 2.4 arcmin wide DSS image of NGC 4553
DSS image of lenticular galaxy NGC 4553
Below, a 3 arcmin wide 2MASS image of the galaxy
DSS image of lenticular galaxy NGC 4553
Below, a 2.0 by 2.4 arcmin image of the galaxy from Ron Buta's deVaucouleurs Atlas website
CTIO/deVaucouleurs Atlas image of lenticular galaxy NGC 4553

NGC 4554
Recorded (1882) by
Wilhelm Tempel
A lost or nonexistent object in Virgo (RA 12 35 41.9, Dec +11 11 11)
Per Dreyer, NGC 4554 (Temple list V, 1860 RA 12 28 37, NPD 78 02.5) is "very faint." The second IC adds "Not found by Frost on plate of 4 hours exposure." The position precesses to RA 12 35 41.9, Dec +11 11 11 (whence the position above), but there is nothing there. Corwin suggests (and Steinicke agrees) that the pair of magnitude 13.4 and 13.6 stars at RA 12 35 59.5, Dec +11 15 55 (about 6 arcmin northeast of the NGC position) might be what Tempel observed, then points out that for that to be true Tempel's recorded offsets from NGC 4567/8 (which are well to the left of the field of view shown below) would have to be off in both direction and size. Since that isn't likely, the double star is almost certainly not NGC 4554, and the NGC entry almost certainly represents a lost or (more likely) nonexistent object.
SDSS image of region centered on Tempel's position for the probably nonexistent NGC 4554; the stars that are sometimes listed as NGC 4554 but are almost certainly not that object are boxed-in for reference
Above, a 12 arcmin wide region centered on Tempel's position for NGC 4554
(The stars that are sometimes listed as NGC 4554 but are almost certainly not NGC 4554 are "boxed-in" for reference)

NGC 4555 (=
IC 3545)
(= PGC 41975 = UGC 7762 = CGCG 159-021 = MCG +05-30-026)

Discovered (Apr 6, 1785) by William Herschel (and later listed as NGC 4555)
Discovered (Mar 23, 1903) by Max Wolf (and later listed as IC 3545)
A magnitude 12.4 elliptical galaxy (type E3?) in Coma Berenices (RA 12 35 41.2, Dec +26 31 23)
Historical Identification: Per Dreyer, NGC 4555 (GC 3099 = JH 1350 = WH II 343, 1860 RA 12 28 43, NPD 62 42.3) is "bright, pretty small, irregularly round, very suddenly much brighter middle equivalent to 12th magnitude star". The position precesses to RA 12 35 40.0, Dec +26 31 23, right on the galaxy, so the identification is certain.
Note About Duplicate Entry: As noted in the entry for IC 3545, Wolf mistook the galaxy to the south of NGC 4555 (PGC 1777936) for NGC 4555 itself, so he thought that the brighter northern object was a new discovery, and Dreyer failed to realize that Wolf's position and description were essentially identical to Herschel's, so NGC 4555 ended up in both the NGC and IC2.
Physical Information: Apparent size 2.1 by 1.4 arcmin? As it happens, PGC 1777936) is not only historically important (as the cause of the duplicate entry), but is probably a physical companion of NGC 4555 as well, so it is discussed in the following entry.
SDSS image of region near elliptical galaxy NGC 4555, also showing PGC 1777936, which is related to the duplicate listing for NGC 4555
Above, a 12 arcmin wide SDSS image centered on NGC 4555, also showing PGC 1777936
Below, a 2.4 arcmin wide SDSS image of the galaxy
SDSS image of elliptical galaxy NGC 4555

PGC 1777936
(= "NGC 4555A")

Not an NGC object but listed here because sometimes called NGC 4555A, and as a probable companion of
NGC 4555
A magnitude 16(?) galaxy (type E3-4?) in Coma Berenices (RA 12 35 41.3, Dec +26 28 57)
Physical Information: Based on a recessional velocity relative to the Cosmic Background Radiation of 7025 km/sec (and H0 = 70 km/sec/Mpc), a straightforward calculation indicates that PGC 1777936 is about 325 to 330 million light-years away, in reasonable agreement with a single redshift-independent distance estimate of about 355 to 360 million light-years. 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 315 to 320 million light-years away at the time the light by which we see it was emitted, about 320 to 325 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 about 0.45 by 0.3 arcmin (from the images below), the galaxy is about 40 to 45 thousand light-years across. As it happens, PGC 1777936's northern neighbor, NGC 4555, has a similar recessional velocity and an identical redshift-independent distance estimate, so they are probably physical companions.
SDSS image of region near NGC 4555, also showing elliptical galaxy PGC 1777936, which is related to the duplicate listing for NGC 4555
Above, a 12 arcmin wide SDSS image centered on NGC 4555, also showing PGC 1777936
Below, a 0.75 arcmin wide SDSS image of PGC 1777936
SDSS image of elliptical galaxy PGC 1777936

WORKING HERE: The region near NGC 4556 contains a number of frequently misidentified galaxies; for that reason it will take some time to sort out everything, and complete posts for NGC 4556 - 4563

NGC 4556 (= PGC 41980, and not = [a number of misidentifications])
Discovered (Apr 11, 1785) by
William Herschel
A 13th-magnitude elliptical galaxy (type E3?) in Coma Berenices (RA 12 35 45.9, Dec +26 54 32)
Per Dreyer, NGC 4556 (GC 3100 = JH 1351 = WH II 380, 1860 RA 12 28 46, NPD 62 18.8) is "faint, pretty large". The position precesses to RA 12 35 42.7, Dec +26 54 53, just northwest of the galaxy and there is nothing else near enough to cause any confusion, so the identification is certain. Despite that (per Corwin) there were some ghastly blunders involving NGC 4563 in modern catalogs that resulted in misidentifications involving IC 3556, NGC 4536 and 4556 (more to follow per Corwin). Apparent size 1.5 by 1.1 arcmin.
SDSS image of elliptical galaxy NGC 4556
Above, a 2.4 arcmin wide closeup of NGC 4556
Below, a 12 arcmin wide region centered on the galaxy, also showing (need correct IDs)
SDSS image of region near elliptical galaxy NGC 4556, also showing (several other galaxies, usually misidentified; need correct IDs)

NGC 4557
Recorded (Apr 22, 1886) by
Guillaume Bigourdan
Three magnitude 14.2, 15.0 and 15.5 stars in Coma Berenices (RA 12 35 49.7, Dec +27 03 14)
Per Dreyer, NGC 4557 (Bigourdan (list II #55), 1860 RA 12 28 53, NPD 62 11.5) is a "nebulous star". The position precesses to RA 12 35 49.6, Dec +27 02 11, an arcmin south of a scattering of faint stars, including the triplet listed above. Per Corwin, Bigourdan's offset relative to NGC 4558 clearly places the object close to the triplet, and the description makes its identification as a stellar object certain. He adds that Wolf clearly observed it as the central of three stars, and therefore uses that star's position for the NGC object, but since Bigourdan must not have resolved the stars he considers the triplet to be object, not just the central star. Corwin notes that the MCG and PGC identifications are wrong (and as a result, so are a number of listings for NGC 4557); for that reason, see NGC 4558.
SDSS image of region near the stars listed as NGC 4557, also showing lenticular galaxy NGC 4558, which is often misidentified as NGC 4557, lenticular galaxy IC 3556, which is often misidentified as NGC 4558, lenticular galaxy IC 3559 and spiral galaxy IC 3560
Above, a 12 arcmin wide region centered on NGC 4557, also showing NGC 4558, IC 3556, 3559 and 3560

NGC 4558 (= PGC 41995 = PGC 42019, and not =
NGC 4557 or IC 3556)
Discovered (Apr 19, 1827) by John Herschel
A 15th-magnitude lenticular galaxy (type S0/a?) in Coma Berenices (RA 12 35 52.6, Dec +26 59 32)
See Corwin. (Often misidentified as NGC 4557; in addition, IC 3556 is often misidentified as NGC 4558.) Apparent size 0.85 by 0.75 arcmin.
SDSS image of lenticular galaxy NGC 4558, which is often misidentified as NGC 4557
Above, a 2.4 arcmin wide closeup of NGC 4558
Below, a 12 arcmin wide region centered on the galaxy (also showing a number of others)
SDSS image of region near lenticular galaxy NGC 4558, which is often misidentified as NGC 4557 (also showing a number of other galaxies, labeled with the most likely NGC/IC identifications as of this posting)

NGC 4559 (= PGC 42002)
Discovered (Apr 11, 1785) by
William Herschel
A 10th-magnitude spiral galaxy (type SAB(rs)cd) in Coma Berenices (RA 12 35 57.6, Dec +27 57 36)
Based on a recessional velocity of 815 km/sec, NGC 4559 is about 38 million light years away. Although peculiar (non-Hubble expansion) velocities could be a substantial part of the recessional velocity, the distance is in good agreement with redshift-independent distance estimates of 25 to 50 million light years. Given that and its apparent size of 10.7 by 4.4 arcmin, the galaxy is about 120 thousand light years across. (Several IC objects (e.g., IC 3550, 3551, 3552, 3554, 3555, 3563 and 3564) are stars superimposed on NGC 4559, or emission regions within the galaxy.)
SDSS image of region near spiral galaxy NGC 4559
Above, an 18 arcmin wide SDSS image centered on NGC 4559
Below, a 12 arcmin wide SDSS image of the galaxy
SDSS image of spiral galaxy NGC 4559
Below, a ? arcmin wide NOAO image of the galaxy (Image Credit Jeff Hapeman/Adam Block/AURA/NSF/NOAO)
NOAO image of spiral galaxy NGC 4559

IC 3592
(= PGC 42097 = "NGC 4559A")

Not an NGC object, but listed here because sometimes called NGC 4559A
A 14th-magnitude spiral galaxy (type Sa??) in Coma Berenices (RA 12 36 53.4, Dec +27 51 43)
For anything else see IC 3592

IC 3593
(= PGC 42098 = "NGC 4559B")

Not an NGC object, but listed here because sometimes called NGC 4559B
A 15th-magnitude spiral galaxy (type SAB(rs)ab?) in Coma Berenices (RA 12 36 53.9, Dec +27 44 57)
For anything else see IC 3593.

IC 3550
(= "NGC 4559C")

Not an NGC object, but listed here because sometimes called NGC 4559C
An emission region in Coma Berenices (RA 12 35 51.9, Dec +27 55 57)
A part of spiral galaxy NGC 4559, which see for images. For anything else see IC 3550.

NGC 4560 (probably =
NGC 4526)
(= PGC 41772)

Discovered (Apr 13, 1784) by William Herschel (and later listed as NGC 4526)
Discovered (Dec 28, 1785) by William Herschel (and later listed as NGC 4560)
A 9th-magnitude lenticular galaxy (type SAB0°?(s)) in Virgo (RA 12 34 03.0, Dec +07 41 58)
The second IC adds "Not found on plate by Schwassmann". (This entry will only contain historical information, for which see Corwin. For anything else see NGC 4526.)

NGC 4561 (=
IC 3569)
(= PGC 42020)

Discovered (Apr 27, 1785) by William Herschel (and later listed as NGC 4561)
Discovered (May 7, 1904) by Royal Frost (and later listed as IC 3569)
A 13th-magnitude spiral galaxy (type SB(rs)dm) in Coma Berenices (RA 12 36 08.2, Dec +19 19 22)
See Corwin about the double listing. Apparent size 1.5 by 1.3 arcmin?

NGC 4562
(= PGC 41955 = "NGC 4565A")

Discovered (1882) by
Wilhelm Tempel (V)
A 13th-magnitude spiral galaxy (type SB(s)dm?) in Coma Berenices (RA 12 35 34.6, +25 50 58)
Historical Identification:
Note About Non-Standard Designation: NGC 4562 is sometimes incorrectly referred to as NGC 4565A, and pointlessly so, since it has a perfectly good NGC designation of its own and isn't even particularly close to NGC 4565. Just another example of the stupidity of using non-standard NGC/IC designations.
Physical Information:
SDSS image of region near spiral galaxy NGC 4562
Above, a 12 arcmin wide SDSS image centered on NGC 4562
Below, a 2.4 arcmin wide SDSS image of the galaxy
SDSS image of spiral galaxy NGC 4562

NGC 4563 (not =
NGC 4536, NGC 4556 or IC 3556)
(= PGC 42030)

Discovered (Apr 13, 1864) by Heinrich d'Arrest
A 15th-magnitude spiral galaxy (type S??) in Coma Berenices (RA 12 36 12.9, Dec +26 56 29)
Despite a good NGC position, modern blunders resulted in conflation with IC 3556, NGC 4556 and NGC 4536 (see Corwin). Apparent size 0.5 by 0.4 arcmin?

NGC 4564 (= PGC 42051)
Discovered (Mar 15, 1784) by
William Herschel
An 11th-magnitude elliptical galaxy (type E6???) in Virgo (RA 12 36 27.0, Dec +11 26 21)
Apparent size 3.5 by 1.5 arcmin? Listed as a member (VCC 1664) of the Virgo Cluster.

NGC 4565 (= PGC 42038)
Discovered (Apr 6, 1785) by
William Herschel
A 10th-magnitude spiral galaxy (type SA(s)b?) in Coma Berenices (RA 12 36 20.8, Dec +25 59 16)
Apparent size 15.8 by 2.1 arcmin? NGC 4565 is about 30 million light-years from our Milky Way galaxy. Dust scattered throughout the disk obscures its light, but the nuclear bulge is clearly visible above and below the dust lanes. A little over 100,000 light-years in diameter, NGC4565 is thought to be nearly identical to our own galaxy, and as a result, it is presumed that our galaxy would look very much like this if seen from the same angle.
SDSS image of spiral galaxy NGC 4565
Above, an 18 arcmin wide region centered on NGC 4565
Below, a ? arcmin wide image of the galaxy (Image Credit Bruce Hugo & Leslie Gaul, Adam Block, NOAO/AURA/NSF)
NOAO image of spiral galaxy NGC 4565

NGC 4562
(= PGC 41955 = "NGC 4565A")

Listed above at correct place but also listed here because sometimes called NGC 4565A
A 13th-magnitude spiral galaxy (type SB(s)dm?) in Coma Berenices (RA 12 35 34.6, +25 50 58)
Warning About Non-Standard Designation: NGC 4562 is one of three galaxies sometimes called "NGC 4565A", "4565B" and "4565C", all of them incorrectly and pointlessly, because each of them has a perfectly good designation of its own, and none of them are particularly close to NGC 4565.) For anything else see NGC 4562.

IC 3546
(= PGC 41976 = "NGC 4565B")

Not an NGC object but listed here since sometimes called NGC 4565B
A 15th-magnitude spiral galaxy (type Sc???) in Coma Berenices (RA 12 35 41.7, Dec +26 13 20)
Warning About Non-Standard Designation: IC 3546 is one of three galaxies sometimes called "NGC 4565A", "4565B" and "4565C", incorrectly and pointlessly, because each of them has a perfectly good designation of its own, and none of them are particularly close to NGC 4565.) For anything else see IC 3546.

IC 3543 (= PGC 41974 = "NGC 4565C")
Not an NGC object but listed here since because sometimes called NGC 4565C
A 16th-magnitude spiral galaxy (type Scd??) in Coma Berenices (RA 12 35 41.4, Dec +26 17 09)
Warning About Non-Standard Designation: One of three galaxies sometimes referred to as "NGC 4565A", "4565B" and "4565C", incorrectly and pointlessly, because each of them has a perfectly good designation of its own, and none of them are particularly close to NGC 4565.) For anything else see IC 3543.

NGC 4566 (= PGC 42007)
Discovered (Apr 2, 1791) by
William Herschel
A 13th-magnitude spiral galaxy (type Sbc??) in Ursa Major (RA 12 36 00.1, Dec +54 13 16)
Apparent size 1.3 by 0.9 arcmin?

NGC 4567 (with
NGC 4568 = the Siamese Twins = the Butterfly Galaxies)
(= PGC 42064 = UGC 7777 = CGCG 070-189 = MCG +02-32-151)

Discovered (Mar 15, 1784) by William Herschel
Also observed (May 2, 1829) by John Herschel
Also observed (Apr 23, 1862) by Heinrich d'Arrest
A magnitude 11.3 spiral galaxy (type (R')SA(rs)bc) in Virgo (RA 12 36 32.7, Dec +11 15 29)
and one of a pair of interacting galaxies (with NGC 4568)
Historical Identification: Per Dreyer, NGC 4567 (= GC 3108 = JH 1358 = JH 1363 = WH IV 8, 1860 RA 12 29 27, NPD 77 58.2) is "very faint, large, north-preceding (northwestern) of double nebula (position angle 160°±)", the other being NGC 4568. The position precesses to RA 12 36 11.8, Dec +11 15 31,about 3.7 arcmin due west of the pair of galaxies listed above, the description fits and there is nothing comparable nearby, so the identification is certain.
Discovery Note: Per Gottlieb, William Herschel's position was poor, so John Herschel recorded the pair as novae (JH 1358 & 1359) at the correct position. However, he also made an observation with a poor position (JH 1363) that "he associated with (WH) IV-8 and IV-9. The error was corrected by d'Arrest (whose notes make it clear that he observed both members of the pair) in an 1863 paper, hence my addition of his name to the discovery credits for both galaxies.
Nickname(s) Note: The pair has long been called the Siamese Twins, but the HST press release calls them the Butterfly Galaxies.
Physical Information: Since this is part of an interacting pair, the best estimate of their distance would be based on the average of their individual distance estimates. Given a recessional velocity relative to the Cosmic Microwave Background of about 2575 km/sec for NGC 4567 and of about 2560 km/sec for NGC 4568, their average recessional velocity of 2565 to 2570 km/sec (and H0 of 70 km/sec), their Hubble Flow distance is about 120 million light-years, in reasonable agreement with redshift-independent distance estimates of about 55 to 110 million light-years, but twice the 60 million light-year distance quoted in the HST and NOIRLab press releases. There is no reason to believe, based on past mistakes in their press releases, that the HST/NOIRLab distance is better than the Hubble Flow distance, but the pair is thought to be part of the Virgo Cluster (NGC 4567 is VCC 1673, and NGC 4568 is VCC 1676), and if they happen to be near the center of the cluster and headed outward, a substantial portion of their recessional velocity could be due to acceleration caused by their fall into and through the center of the Cluster. Because of that, in the rest of this paragraph I take both the 60 and 120 million light-year distance estimates into account. Given its apparent size of about 3.65 by 2.3 arcmin for the main galaxy and its brighter outline, and about 4.45 by 3.2 arcmin counting the faint partial ring to its west and southwest (from the images below), the main part of NGC 4567 is about 60 to 65 thousand light-years across if it is at the closer distance, and 125 to 130 thousand light-years across if it is at the further distance, and its outer regions span about 75 to 80 thousand light-years if at the closer distance, and about 155 thousand light-years at the further one.
SDSS image of region near spiral galaxies NGC 4567 and 4568, the Siamese Twins
Above, a 12 arcmin wide SDSS image centered on NGC 4567 and 4568
Below, a 5 arcmin wide SDSS image of the pair
SDSS image of spiral galaxies NGC 4567 and 4568, the Siamese Twins
Below, a 3.5 by 4 arcmin wide image of the pair
(Image Credit Bill & Marian Wallace/Adam Block/AURA/NSF/NOAO)
NOAO image of spiral galaxies NGC 4567 and 4568, the Siamese Twins
Below, a 4.75 arcmin wide image of the pair and a 2020 supernova caught in the act
(Image Credit NASA, ESA, Ryan Foley (UC Santa Cruz), Joseph DePasquale (STScI)))
HST image of spiral galaxies NGC 4567 and 4568, the Siamese Twins, also showing an inset of the 2020 supernova
Below, a 3.0 by 4.5 arcmin version of the image above, only showing the two galaxies (Image Credit as above)
HST image of spiral galaxies NGC 4567 and 4568, the Siamese Twins
Below, a 2.5 by 2.25 arcmin wide image of NGC 4567 and part of 4568 (Image Credit as above)
HST image of spiral galaxy NGC 4567, one of the Siamese Twins
Below, a 5.25 by 5.75 arcmin wide 2022 image of the pair
(Image Credit International Gemini Observatory/NOIRLab/NSF/AURA; Image processing (all from NSF’s NOIRLab)
T.A. Rector (Univ. of Alaska Anchorage), J. Miller (Gemini Observatory), M. Zamani & D. de Martin

NOIRLab/Gemini Observatory image of the pair of interacting spiral galaxies, NGC 4567 and 4568
Below, a 5.0 by 3.5 arcmin wide image of NGC 4567 and part of NGC 4568 (Image Credit as above)
NOIRLab/Gemini Observatory image of the spiral galaxy NGC 4567 and part of NGC 4568

NGC 4568 (with
NGC 4567 = the Siamese Twins = the Butterfly Galaxies)
(= PGC 42069 = UGC 7776 = CGCG 070-188 = MCG +02-32-152)

Discovered (Mar 15, 1784) by William Herschel
Also observed (May 2, 1829) by John Herschel
Also observed (Apr 23, 1862) by Heinrich d'Arrest
A magnitude 10.8 spiral galaxy (type SA(rs)bc) in Virgo (RA 12 36 34.3, Dec +11 14 20)
and one of a pair of interacting galaxies (with NGC 4567)
Historical Identification: Per Dreyer, NGC 4568 (= GC 3109 = JH 1359 = JH 1363 = WH IV 9, 1860 RA 12 29 29, NPD 77 59.4) is "very faint, large, south-following (southeastern) of double nebula (position angle 160 °±)," the other being NGC 4567. The position precesses to RA 12 36 13.8, Dec +11 14 19, about 3.6 arcmin due west of the galaxy listed above, but the description fits and there is nothing comparable nearby, so the identification is certain.
Discovery Note: Per Gottlieb, William Herschel's position was poor, so John Herschel recorded the pair as novae (JH 1358 & 1359) at the correct position. However, he also made an observation with a poor position (JH 1363) that "he associated with (WH) IV-8 and IV-9. The error was corrected by d'Arrest (whose notes make it clear that he observed both members of the pair) in an 1863 paper, hence my addition of his name to the discovery credits for both galaxies.
Nickname(s) Note: The pair has long been called the Siamese Twins, but the HST press release calls them the Butterfly Galaxies.
Physical Information: Since NGC 4568 is part of an interacting pair, the best estimate of its (and their) distance is based on an average of their individual data. As shown in detail in the entry for NGC 4567, the pair is either about 120 million light-years away, a little beyond the outer border of the Virgo Cluster (of which they are thought to be members; also see NGC 4567 for that), or 60 million light-years away, near the center of the Cluster but rapidly moving outward as a result of an acceleration caused by their falling from the near border of the Cluster, toward the center and beyond. Because of that, the rest of this paragraph uses both possible distances. Given its apparent size of about 5.1 by 1.75 arcmin (from the images below and following the entry for NGC 4567), NGC 4568 is about 90 thousand light-years across if the pair ia 60 million light-years away, and about 175 to 180 thousand light-years across if it ia 120 million light-years away.
HST image of interacting spiral galaxies NGC 4567 and NGC 4568, also known as The Siamese Twins
Above, a 3.0 by 4.5 arcmin wide image of 4567 and NGC 4568, and a 2020 supernova in NGC 4568
(Image Credit NASA, ESA, Ryan Foley (UC Santa Cruz), Joseph DePasquale (STScI))
(For wider-field and other images, see NGC 4567)

Below, a 3.75 by 5.25 arcmin wide image of NGC 4568 and most of NGC 4567
(Image Credit International Gemini Observatory/NOIRLab/NSF/AURA; Image processing (all from NSF’s NOIRLab)
T.A. Rector (Univ. of Alaska Anchorage), J. Miller (Gemini Observatory), M. Zamani & D. de Martin

NOIRLab/Gemini Observatory image of the spiral galaxy NGC 4568 and part of NGC 4567

NGC 4569 (=
M90, and with IC 3583 = Arp 76)
(= PGC 42089)

Discovered (Mar 18, 1781) by Charles Messier and recorded as M90
A magnitude 9.5 spiral galaxy (type SAB(rs)ab?) in Virgo (RA 12 36 49.8, Dec +13 09 47)
Historical Identification: Per Dreyer, NGC 4569 (= GC 3111, M90, 1860 RA 12 29 46, NPD 76 03.9) is "pretty large, brighter middle and nucleus". The position precesses to RA 12 36 49.8, Dec +3 09 49, essentially dead center on the galaxy listed above and the description fits, so the identification is certain.
Physical Information: The recessional velocity of NGC 4569 is -235 km/sec (in other words, it is approaching us instead of moving away from us, as most galaxies are). Such a velocity normally applies only to objects very close to us, and most early estimates of its distance put it relatively close to or even within the outer reaches of our Local Group. However, it is listed as a member (VCC 1692) of the Virgo Cluster, which is about 60 million light years away, and the reason for its odd radial velocity is probably that the Local Group happens to be moving in the direction of that cluster at about 600 km/sec, so that most of the galaxies in that region have unusually low or even negative recessional velocities. (There is also a large range of motions within massive clusters such as the Virgo Cluster (so-called peculiar velocities, or real motions of the galaxies relative to each other, as opposed to the apparent motion associated with the expansion of the Universe), and even without the motion of the Local Group some of the members of the Virgo Cluster moving toward us relative to the Cluster as a whole would still have small or negative radial velocities.) Even redshift-independent distance estimates, perhaps partly influenced by earlier views concerning its distance, are mostly in the range of 30 to 35 million light years; but as noted above, as a member of the Virgo Cluster, it must be about 60 million light years away, and although the current 'best' guess is just under that, the uncertainty overlaps the rounded off value. This entry therefore adopts 60 million light years as the distance, in which case the galaxy's apparent size of 9.5 by 4.4 arcmin would make it about 165 thousand light years across. NGC 4569 is listed in Arp's Atlas of Peculiar Galaxies, as part of Arp 76. The closeup of the galaxy omits its apparent companion, but the mid-range and wide-field images also show IC 3583.
SDSS image of region near spiral galaxy NGC 4569, also known as M90, also showing IC 3583, with which it comprises Arp 76
Above, a 16 arcmin wide SDSS image centered on NGC 4569, also showing IC 3583, with which it comprises Arp 76
Below, a 10 arcmin wide SDSS image of NGC 4569, also known as M90
SDSS image of spiral galaxy NGC 4569, also known as M90, and as the major component of Arp 76
Below, a ? arcmin wide view of M90 (Image Credit Paul & Daniel Koblas/Adam Block/AURA/NSF/NOAO)
NOAO image of spiral galaxy NGC 4569, also known as M90, and the major component of Arp 76
Below, a ? arcmin wide view of Arp 76 (Image Credit AURA/NSF/NOAO)
NOAO image of spiral galaxy NGC 4569, also known as M90, and IC 3583, with which it comprises Arp 76

NGC 4570 (= PGC 42096)
Discovered (Apr 13, 1784) by
William Herschel
An 11th-magnitude lenticular galaxy (type S0??) in Virgo (RA 12 36 53.4, Dec +07 14 48)
Apparent size 3.7 by 1.2 arcmin?

NGC 4571 (=
IC 3588)
(= PGC 42100 = UGC 7788 = CGCG 070-194 = MCG +02-32-156)

Discovered (Jan 14, 1787) by William Herschel (and later listed as NGC 4571)
Also observed (Apr 3, 1826) by John Herschel (and later listed as NGC 4571)
Also observed (Dec 29, 1861) by Heinrich d'Arrest (and later listed as NGC 4571)
Discovered (Nov 23, 1900) by Arnold Schwassmann (and later listed as IC 3588)
A magnitude 11.3 spiral galaxy (type SA(r)c) in Coma Berenices (RA 12 36 56.4, Dec +14 13 02)
Historical Identification: Per Dreyer, NGC 4571 (= GC 3113 = JH 1362 = WH III 602, M 91??, d'Arrest, 1860 RA 12 29 50, NPD 75 01.7) is "very faint, large, extended, very gradually brighter middle, 9th magnitude star near north-following (to the northeast)." The position precesses to RA 12 36 53.2, Dec +14 12 01, only about 1.3 arcmin southwest of the center of the galaxy listed above, and well within its overall outline; the description fits (and the magnitude 8.9 star, BD+15 2483, is exactly where stated) and there is nothing else nearby, so the identification is certain. However, Dreyer's obviously uncertain suggestion that it might be the long-missing M91 (NGC 4548, which see) was definitely wrong (as were several later suppositions about the identity of that object), as NGC 4571 is too faint for Messier to have seen with his small instrument.
Discovery Note: Per Corwin, although the NGC position was good, Schwassmann misidentified the star superimposed on the western side of the galaxy as NGC 4571, and therefore listed the faint object to its left (the core of the actual galaxy) as a "nova", leading to the duplicate (IC2) entry.
Physical Information: NGC 4571's recessional velocity relative to the Cosmic Microwave Background is really too small to be a reasonably certain indicator of its distance, because as a member of the Virgo Cluster (VCC 1696) its "peculiar velocity" (its random motion relative to its neighbors) could be a substantial fraction of its overall velocity, and using its value of about 655 km/sec (and H0 = 70 km/sec/Mpc) yields a distance of only about 30 million light-years, considerably less than redshift-independent distance estimates of about 40 to 70 million light-years and the HST press release's "approximately 60 million light-years", so the HST estimate is probably a best guess for now (future studies of stars in the galaxy should provide a value deserving greater confidence). Given that and its apparent size of about 3.5 by 3.3 arcmin (from the images below), the galaxy is about 60 to 65 thousand light-years across.
Use By The deVaucouleurs Atlas: NGC 4571 is used by The deVaucouleurs Atlas of Galaxies as an example of type SA(r)c, the (r) referring to the ring around its core. LEDA uses essentially the same classification, while NED uses the slightly less organized classification SA(r)d, but the images shown here make me tend to agree with the deVaucouleurs atlas.
SDSS image of region near spiral galaxy NGC 4571
Above, a 12 arcmin wide SDSS image centered on NGC 4571
Below, a 4 arcmin wide SDSS image of the galaxy
SDSS image of spiral galaxy NGC 4571
Below, a 2.5 by 2.75 arcmin wide image of the galaxy (Image Credit PHANGS-HST, Judy Schmidt; used by permission)
PHANGS-HST image of spiral galaxy NGC 4571, also listed as IC 3588; image processing by Judy Schmidt (geckzilla)
Below, a similar 3.0 by 3.25 arcmin wide image of the galaxy (Image Credit ESA/Hubble & NASA, J. Lee and the PHANGS-HST Team))
HST image of spiral galaxy NGC 4571, also listed as IC 3588
Below, a 1.5 arcmin wide image of the central region (Image Credit as above)
HST image of central region of spiral galaxy NGC 4571, also listed as IC 3588

NGC 4572 (= PGC 41991)
Discovered (Dec 10, 1797) by
William Herschel
A 14th-magnitude spiral galaxy (type S??) in Draco (RA 12 35 45.9, Dec +74 14 44)
The first IC notes "RA is 12 30 30 (per Bigourdan), which agrees better with William Herschel (12 30 18) than with John". Per Corwin (which see), Bigourdan's position actually refers to a star southeast of the galaxy. Apparent size 1.5 by 0.3 arcmin?

NGC 4573 (= PGC 42167)
Discovered (Mar 15, 1836) by
John Herschel
A 13th-magnitude lenticular galaxy (type (R)SB0/a(rs)) in Centaurus (RA 12 37 43.8, Dec -43 37 16)
Apparent size 2.5 by 1.9 arcmin?

NGC 4574 (= PGC 42166)
Discovered (Apr 20, 1835) by
John Herschel
A 13th-magnitude spiral galaxy (type SAB(s)c) in Centaurus (RA 12 37 43.5, Dec -35 31 03)
Apparent size 1.8 by 1.1 arcmin?

NGC 4575 (= PGC 42181)
Discovered (Jun 8, 1834) by
John Herschel
A 13th-magnitude spiral galaxy (type SB(s)bc pec?) in Centaurus (RA 12 37 51.1, Dec -40 32 14)
Apparent size 2.0 by 1.2 arcmin?

NGC 4576 (= PGC 42152)
Discovered (Apr 27, 1881) by
Edward Holden (7)
A 14th-magnitude spiral galaxy (type SAB(rs)bc?) in Virgo (RA 12 37 33.6, Dec +04 22 04)
Apparent size 1.2 by 0.8 arcmin? Listed as a member (VCC 1721) of the Virgo Cluster.

NGC 4577 (probably =
NGC 4591)
(= PGC 42319)

Discovered (Jan 28, 1784) by William Herschel (and later listed as NGC 4577)
Discovered (Feb 2, 1786) by William Herschel (and later listed as NGC 4591)
A 13th-magnitude spiral galaxy (type Sab??) in Virgo (RA 12 39 12.4, Dec +06 00 44)
Refer to Corwin for the double listing. Apparent size 1.6 by 0.8 arcmin? Listed as a member (VCC 1780) of the Virgo Cluster.

NGC 4578 (= PGC 42149)
Discovered (Jan 18, 1784) by
William Herschel
A 12th-magnitude lenticular galaxy (type SA0°(r)?) in Virgo (RA 12 37 30.6, Dec +09 33 18)
Apparent size 3.1 by 2.3 arcmin? Listed as a member (VCC 1720) of the Virgo Cluster.

NGC 4579 (=
M58 = PGC 42168)
Discovered (Apr 15, 1779) by Charles Messier and recorded as M58
Also observed (May 9, 1825) by John Herschel
A magnitude 9.7 spiral galaxy (type SAB(rs)b?) in Virgo (RA 12 37 43.5, Dec +11 49 06)
Apparent size 6.0 by 4.8 arcmin? Listed as a member (VCC 1727) of the Virgo Cluster.
SDSS image of region near spiral galaxy NGC 4579, also known as M58
Above, a 12 arcmin wide SDSS image centered on NGC 4579
Below, a ? arcmin wide image of NGC 4579 (Steve Mandel/Adam Block/AURA/NSF/NOAO)
NOAO image of spiral galaxy NGC 4579, also known as M58

NGC 4580 (= PGC 42174)
Discovered (Feb 2, 1786) by
William Herschel
A 12th-magnitude spiral galaxy (type SAB(rs)a pec?) in Virgo (RA 12 37 48.4, Dec +05 22 07)
(Referred to by Corwin in a discussion of the identification of NGC 4577.) Apparent size 2.1 by 1.5 arcmin? Listed as a member (VCC 1730) of the Virgo Cluster.

NGC 4581 (= PGC 42199)
Discovered (Apr 20, 1882) by
Edward Holden (24)
A 13th-magnitude elliptical galaxy (type E4???) in Virgo (RA 12 38 05.2, Dec +01 28 40)
Apparent size 1.9 by 1.1 arcmin?

APMUKS(BJ) B123533.53+014438.5
Not an NGC object but listed here as an apparent companion of
NGC 4581
A magnitude 20(?) galaxy(?) (type ?) in Virgo RA 12 38 07.1, Dec +01 28 09
Corwin lists this faint fuzzball as an apparent companion of NGC 4581, but it is apparently listed only in NED, and other than its position and magnitude (whence the description line), even that site has nothing to say about the object, so this "entry" may well be pointless.

NGC 4582
Recorded (May 3, 1859) by
Sidney Coolidge (15, HN 20)
A magnitude 13.2 star in Virgo (RA 12 38 10.1, Dec +00 10 58)
Refer to Corwin.
SDSS image of region near the star listed as NGC 4582
Above, a 12 arcmin wide SDSS image centered on the star listed as NGC 4582

NGC 4583 (= PGC 42198)
Discovered (Jan 2, 1786) by
William Herschel
A 13th-magnitude lenticular galaxy (type SB0/a?) in Canes Venatici (RA 12 38 04.6, Dec +33 27 32)
Apparent size 1.1 by 0.9 arcmin?

NGC 4584 (= PGC 42223)
Discovered (Apr 21, 1862) by
Heinrich d'Arrest
A 13th-magnitude spiral galaxy (type SAB(s)a?) in Virgo (RA 12 38 17.9, Dec +13 06 36)
Apparent size 1.4 by 1.0 arcmin? Listed as a member (VCC 1757) of the Virgo Cluster.

NGC 4585 (= PGC 42215)
Discovered (Apr 21, 1865) by
Heinrich d'Arrest
A 14th-magnitude spiral galaxy (type SBb??) in Coma Berenices (RA 12 38 13.3, Dec +28 56 13)
Apparent size 0.7 by 0.4 arcmin?

NGC 4586 (= PGC 42241)
Discovered (Feb 2, 1786) by
William Herschel
A 12th-magnitude spiral galaxy (type SA(s)a?) in Virgo (RA 12 38 28.4, Dec +04 19 09)
Apparent size 3.8 by 1.2 arcmin? Listed as a member (VCC 1760) of the Virgo Cluster.

NGC 4587 (= PGC 42253)
Discovered (Apr 17, 1882) by
Johann Palisa
A 14th-magnitude lenticular galaxy (type SA0°(r)?) in Virgo (RA 12 38 35.4, Dec +02 39 26)
Apparent size 1.1 by 0.5 arcmin? Listed as a member (VCC 1763) of the Virgo Cluster.

NGC 4588 (= PGC 42277)
Discovered (Apr 13, 1784) by
William Herschel
A 14th-magnitude spiral galaxy (type Scd??) in Virgo (RA 12 38 45.4, Dec +06 46 05)
Apparent size 1.3 by 0.4 arcmin? Listed as a member (VCC 1772) of the Virgo Cluster.

NGC 4589 (= PGC 42139)
Discovered (Nov 22, 1797) by
William Herschel
An 11th-magnitude elliptical galaxy (type E2??) in Draco (RA 12 37 25.0, Dec +74 11 31)
Apparent size 3.4 by 2.8 arcmin?

NGC 4590 (=
M68 = GCL 20)
Discovered (Apr 9, 1780) by Charles Messier
A 7th-magnitude globular cluster (type X) in Hydra (RA 12 39 28.3, Dec -26 44 33)
Apparent size 11 arcmin? Approximately 35 thousand light years away, and 100 light years in diameter.
DSS image of region near globular cluster NGC 4590, also known as M68
Above, a 12 arcmin wide DSS image centered on NGC 4590
Below, a (3.32 arcmin?) image of the core of the cluster (Image Credit HST, NASA, ESA, WikiSky)
HST image of core of globular cluster NGC 4590, also known as M68
(A better (3.4 arcmin?) HST image is here)

NGC 4591 (probably =
NGC 4577)
(= PGC 42319)

Discovered (Jan 28, 1784) by William Herschel (and later listed as NGC 4577)
Discovered (Feb 2, 1786) by William Herschel (and later listed as NGC 4591)
A 13th-magnitude spiral galaxy (type Sab??) in Virgo (RA 12 39 12.4, Dec +06 00 44)
Refer to Corwin for a discussion of the double listing. Apparent size 1.6 by 0.8 arcmin? Listed as a member (VCC 1780) of the Virgo Cluster.

NGC 4592 (= PGC 42336)
Discovered (Feb 23, 1784) by
William Herschel
A 12th-magnitude spiral galaxy (type SA(s)dm?) in Virgo (RA 12 39 18.8, Dec -00 31 56)
Apparent size 5.2 by 1.35 arcmin.
SDSS image of region near spiral galaxy NGC 4592
Above, a 12 arcmin wide SDSS image centered on NGC 4592
Below, a 6 arcmin wide SDSS image of the galaxy
SDSS image of spiral galaxy NGC 4592
Below, a ? arcmin wide image of the galaxy (North at right to allow for more detail)
(Image Credit Hubble Legacy Archive, Acknowledgment Stephen Byrne)
HST image of spiral galaxy NGC 4592

NGC 4593 (= PGC 42375)
Discovered (Apr 17, 1784) by
William Herschel
An 11th-magnitude spiral galaxy (type (R)SB(rs)b) in Virgo (RA 12 39 39.4, Dec -05 20 39)
Apparent size 3.9 by 2.9 arcmin?

NGC 4594 (=
M104), The Sombrero Galaxy
(= PGC 42407)

Discovered (May 11, 1781) by Pierre Méchain
Méchain's discovery was noted by Charles Messier, but was not added to his Catalog
Discovered (May 9, 1784) by William Herschel
Also observed (Mar 9, 1828) by John Herschel
Appended (1921) to the Messier Catalog by Camille Flammarion as M104
A magnitude 8.0 spiral galaxy (type SA(s)a?) in Virgo (RA 12 39 59.4, Dec -11 37 23)
Historical Identification: Per Dreyer, NGC 4594 (= GC 3132 = JH 1376 = WH I 43, 1860 RA 12 32 43, NPD 100 51.2) is "a remarkable object, very bright, very large, extremely extended 92°, very suddenly much bright middle and nucleus". The position precesses to RA 12 39 59.2, Dec -11 37 23, right on the galaxy listed above, so the identification is certain.
Discovery Notes (as M104): Although Méchain discovered this nebula in 1781, his first known correspondence (to Bernoulli) was on May 6, 1783. Méchain probably also communicated with Messier at some earlier date, but it must have been too late for Messier to add it to his Catalog, as his only reference to Méchain's discovery was a handwritten note in his copy of the Connoissance des Temps for 1784. Its prior discovery appears to have been unknown to either of the Herschels or to Dreyer, leading to the lack of any mention of Méchain or Messier in the NGC entry. However, in 1917 Camille Flammarion noted the earlier observations, and given the fact that they were made at essentially the same time Messier finished his Catalog, suggested adding the nebula to Messier's catalog as M104; and it has been treated as such ever since.
Physical Information: Apparent size 8.6 by 4.2 arcmin? (Rather oddly, not listed as a member of the Virgo Cluster in the VCC; redshift-independent distance estimates range from 20 to 65 million light years, with a median of 30 million light years; so perhaps in front of the Cluster, instead of "at its nearer edge" as stated immediately following.) M104 lies at the nearer edge of the 60 million light year distant Virgo cluster of galaxies, and at nearly a trillion solar masses is one of the more massive galaxies in that group, even though relatively small (about 50 thousand light years across). The massive central bulge of the galaxy almost totally obscures the structure of the spiral disk, but a recent reworking of this image, seen on a separate page about M104, reduces the glare from the nucleus, better revealing the spiral structure.
SDSS image of region near spiral galaxy NGC 4594, also known as the Sombrero Galaxy, M104
Above, a 12 arcmin wide SDSS image centered on M104
Below, a labeled view of the image above (labeling and artifact removal still in progress)
Labeled image of region near spiral galaxy NGC 4594, also known as the Sombrero Galaxy, M104
Below, a ? arcmin wide HST image of M104 (The Hubble Heritage Team (STScI/AURA), NASA)
HST image of spiral galaxy NGC 4594, also known as the Sombrero Galaxy, M104
Below, a Spitzer/HST infrared/visible composite (Credit JPL-Caltech/University of Arizona/STScI/NASA)
Spitzer/HST false-color composite of spiral galaxy NGC 4594, also known as the Sombrero Galaxy, M104

NGC 4595 (= PGC 42396)
Discovered (Jan 14, 1787) by
William Herschel
A 12th-magnitude spiral galaxy (type SAB(rs)b?) in Coma Berenices (RA 12 39 51.9, Dec +15 17 52)
Apparent size 1.7 by 1.1 arcmin? Listed as a member (VCC 1811) of the Virgo Cluster.

NGC 4596 (= PGC 42401)
Discovered (Mar 15, 1784) by
William Herschel
A 10th-magnitude lenticular galaxy (type SB0+(r)) in Virgo (RA 12 39 56.0, Dec +10 10 34)
Apparent size 4.0 by 3.0 arcmin? Listed as a member (VCC 1813) of the Virgo Cluster.

NGC 4597 (= PGC 42429)
Discovered (Feb 22, 1787) by
William Herschel
A 12th-magnitude spiral galaxy (type SB(rs)m) in Virgo (RA 12 40 12.4, Dec -05 47 58)
Apparent size 4.1 by 1.9 arcmin?

NGC 4598 (= PGC 42427)
Discovered (Apr 15, 1784) by
William Herschel
A 13th-magnitude lenticular galaxy (type SB0??) in Virgo (RA 12 40 11.9, Dec +08 23 02)
Apparent size 1.4 by 1.1 arcmin? Listed as a member (VCC 1827) of the Virgo Cluster.

NGC 4599 (= PGC 42453)
Discovered (Feb 22, 1786) by
William Herschel
A 13th-magnitude lenticular galaxy (type SA0/a?) in Virgo (RA 12 40 27.1, Dec +01 11 49)
Apparent size 1.7 by 0.8 arcmin?
Celestial Atlas
(NGC 4500 - 4549) ←NGC Objects: NGC 4550 - 4599→ (NGC 4600 - 4649)