Celestial Atlas
(IC 1550 - 1599) ←IC Objects: IC 1600 - 1649→ (IC 1650 - 1699)
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1600, 1601, 1602, 1603, 1604, 1605, 1606, 1607, 1608, 1609, 1610, 1611, 1612, 1613, 1614, 1615, 1616,
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Page last updated Aug 22, 2023 (Caldwell & other IDs added for IC 1613)
Page last updated June 23, 2021
Updated & completed 1623
Updated formatting to current standards
Added Corwin positions, Dreyer entries
WORKING 1601: Check companions, types, add basic pix, captions, tags

IC 1600
(= PGC 3253 = ESO 474-043 = MCG -04-03-031)

Discovered (Nov 3, 1898) by
DeLisle Stewart
A magnitude 14.8 spiral galaxy (type Sbc?) in Cetus (RA 00 55 04.2, Dec -23 31 30)
Historical Identification: Per Dreyer, IC 1600 (DeLisle Stewart #128, 1860 RA 00 48 14, NPD 114 17) is "very faint, very small, considerably extended 95°."
Physical Information: Based on a recessional velocity of 11725 km/sec, a straightforward calculation indicates that IC 1600 is about 545 million light-years away. However, for objects at such distances we should take into account the Universal expansion during the time it took their light to reach us. Doing that shows that the galaxy was about 520 million light-years away at the time the light by which we see it was emitted, a little over 530 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 0.7 by 0.45 arcmin, it is about 105 thousand light-years across. (Note to self: Directly checked per final protocols.)
DSS image of region near spiral galaxy IC 1600
Above, a 12 arcmin wide DSS image centered on IC 1600
Below, a 2.4 arcmin wide DSS image of the galaxy
DSS image of spiral galaxy IC 1600

IC 1601
(= PGC 3287 = ESO 474-044 = MCG -04-03-032)

Discovered (Nov 3, 1898) by
DeLisle Stewart
A magnitude 13.7 spiral galaxy (type Sab??) in Cetus (RA 00 55 34.8, Dec -24 09 13)
Historical Identification: Per Dreyer, IC 1601 (DeLisle Stewart #129, 1860 RA 00 48 44, NPD 114 55) is "very faint, very small, a little extended 105°."
Physical Information: Apparent size 0.9 by 0.4 arcmin?

IC 1602
(= PGC 3306 = MCG -02-03-047)

Discovered (Dec 16, 1898) by
Herbert Howe
A magnitude 14.3 elliptical galaxy (type E1??) in Cetus (RA 00 55 51.9, Dec -09 59 08)
Historical Identification: Per Dreyer, IC 1602 (Howe list II (#1), 1860 RA 00 48 49, NPD 100 44.7) is "very faint, small, near 309," 309 being NGC 309.
Physical Information: Apparent size 0.7 by 0.6 arcmin?

IC 1603
(= PGC 3401 = ESO 243-014)

Discovered (1899) by
DeLisle Stewart
A magnitude 13.8 spiral galaxy (type Sc??) in Phoenix (RA 00 56 59.7, Dec -45 24 46)
Historical Identification: Per Dreyer, IC 1603 (DeLisle Stewart #130, 1860 RA 00 50 34, NPD 136 11) is "extremely faint, extremely small, considerably extended 115°, considerably brighter middle."
Physical Information: Apparent size 1.3 by 0.8 arcmin?

IC 1604
Recorded (Nov 19, 1898) by
Lewis Swift
A lost or nonexistent object in Cetus (RA 00 58 00.0, Dec -16 13 00)
Historical Identification: Per Dreyer, IC 1604 (Swift list XII (#4), 1860 RA 00 51 01), NPD 107±) is "pretty faint, very small, 7.5 magnitude star north-preceding (to northwest), faint star near south-preceding (southwest) [= 333?]," 333 being NGC 333.
Corwin suggests a possible identification (though with doubled question marks) at RA 00 58 58.0, Dec -16 44 34
Physical Information:

IC 1605
(= PGC 3436 = PGC 138289 = ESO 195-019)

Discovered (1899) by
DeLisle Stewart
A magnitude 12.9 spiral galaxy (type SBbc??) in Phoenix (RA 00 57 37.6, Dec -48 54 10)
Historical Identification: Per Dreyer, IC 1605 (DeLisle Stewart #131, 1860 RA 00 51 17, NPD 139 40) is "very faint, extremely small, round."
Physical Information: Apparent size 1.6 by 1.3 arcmin?

IC 1606
Recorded (Sep 14, 1895) by
Lewis Swift
A lost or nonexistent object in Cetus (RA 00 58 22.3, Dec -12 10 47)
Historical Identification: Per Dreyer, IC 1606 (Swift list XI (#7), 1860 RA 00 51 22, NPD 102 56.2) is "extremely faint, pretty small, nearly between 7th magnitude star preceding (to west) and 9th magnitude star north-following (to northeast)."
Corwin suggests a possible identification (though with doubled question marks) at RA 00 56 00.2, Dec -12 33 01
Physical Information:

IC 1607
(= PGC 3512 = UGC 611 = CGCG 384-051 = MCG +00-03-047)

Discovered (Jun 24, 1895) by
Herbert Howe
Discovered (date?) by Stephane Javelle
A magnitude 13.4 spiral galaxy (type S??) in Cetus (RA 00 58 48.9, Dec +00 35 14)
Historical Identification: Per Dreyer, IC 1607 (Howe list I (#3), Javelle #830, 1860 RA 00 51 38, NPD 90 10.2) is "very faint, pretty small, round, a little brighter middle."
Physical Information: Apparent size 0.9 by 0.9 arcmin?

IC 1608
(= PGC 3549 = ESO 351-027 = MCG -06-03-013)

Discovered (Oct 3, 1897) by
Lewis Swift
A magnitude 12.4 lenticular galaxy (type S0/a??) in Sculptor (RA 00 59 24.4, Dec -34 19 44)
Historical Identification: Per Dreyer, IC 1608 (Swift list XI (#8), 1860 RA 00 52 36, NPD 125 04.5) is "pretty bright, pretty small, round; 2 stars north-following (to northeast), 2 north-preceding (to northwest)."
Physical Information: Apparent size 2.0 by 0.9 arcmin?

IC 1609
(= PGC 3567 = ESO 295-026 = MCG -07-03-004)

Discovered (Sep 4, 1897) by
Lewis Swift
A magnitude 12.6 lenticular galaxy (type S0??) in Phoenix (RA 00 59 46.6, Dec -40 20 01)
Historical Identification: Per Dreyer, IC 1609 (Swift list XI (#9), 1860 RA 00 53 08, NPD 131 06.9) is "very faint, very small, round."
Physical Information: Apparent size 1.4 by 1.4 arcmin?

IC 1610
(= PGC 3681 = MCG -03-03-020)

Discovered (Dec 13, 1895) by
Lewis Swift
Also observed (date?) by Herbert Howe
A magnitude 12.9 lenticular galaxy (type S0/a??) in Cetus (RA 01 01 42.6, Dec -15 34 04)
Historical Identification: Per Dreyer, IC 1610 (Swift list XI (#10), Howe, 1860 RA 00 54 45, NPD 106 19.3) is "pretty faint, pretty small, round, 10th magnitude star north-preceding (to northwest)."
Physical Information: Apparent size 1.4 by 1.0 arcmin?

IC 1611 (an OCL in the Small Magellanic Cloud)
(= "PGC 3518508")

Discovered (Sep 2, 1826) by
James Dunlop
Discovered (Nov 27, 1900) by DeLisle Stewart
A magnitude 12.0 open cluster in Tucana (RA 00 59 48.0, Dec -72 20 01)
Historical Identification: Per Dreyer, IC 1611 (DeLisle Stewart #132, (Dunlop #26), 1860 RA 00 55 03, NPD 163 06) is "very faint, brighter middle."
Discovery Note: At the time the IC2 was published, Dunlop's discoveries were not trusted in Europe, unless confirmed by John Herschel in the 1830's. However, it is now felt certain that his #26 was an observation of the open clusters IC 1611 and 1612, hence the credit given to him above, and the insertion of his observation (in parentheses) in the IC entry.
Note About PGC Designation: For the sake of completeness LEDA assigns PGC designations to many NGC/IC objects that are not galaxies. In this case, a search of the database for that designation does not return a result, hence its being placed in quotes.
Physical Information: Apparent size 1.0 arcmin?

IC 1612 (an OCL in the Small Magellanic Cloud)
(= "PGC 3518509")

Discovered (Sep 5, 1826) by
James Dunlop
Discovered (date?) by DeLisle Stewart
A magnitude 12.5 open cluster in Tucana (RA 01 00 01.4, Dec -72 22 07)
Historical Identification: Per Dreyer, IC 1612 (DeLisle Stewart #133, (Dunlop #26), 1860 RA 00 55 21, NPD 163 08) is "extremely faint, very small."
Discovery Note: At the time the IC2 was published, Dunlop's discoveries were not trusted in Europe, unless confirmed by John Herschel in the 1830's. However, it is now felt certain that his #26 was an observation of the open clusters IC 1611 and 1612, hence the credit given to him above, and the insertion of his observation (in parentheses) in the IC entry.
Note About PGC Designation: For the sake of completeness LEDA assigns PGC designations to many NGC/IC objects that are not galaxies. In this case, a search of the database for that designation does not return a result, hence its being placed in quotes.
Physical Information: Apparent size 0.7 arcmin?

IC 1613
(
C51 = PGC 3844 = UGC 668 = CGCG 384-068 = MCG +00-03-070)
Discovered (September, 1906) by Max Wolf
A magnitude 9.2 irregular galaxy (type IB(s)m) in Cetus (RA 01 04 47.8, Dec +02 07 04)
Historical Identification: Per Dreyer, IC 1613 (Wolf, 1860 RA 00 56 00, NPD 88 48) is "faint, most extremely large."
Physical Information: IC 1613 is a member of the Local Group. Its recessional velocity is -235 km/sec, and therefore completely useless for estimating the distance a not unusual situation for nearby galaxies, for which peculiar (non-Hubble expansion) velocities are often larger than the Hubble expansion velocity. Redshift-independent distance estimates range from 2.1 to 2.6 million light-years, yielding a statistically averaged distance of 2.3 to 2.45 million light-years. Given that and its apparent size of 16.2 by 14.5 arcmin, the galaxy is about 11 thousand light-years across, and is therefore considered a "dwarf". Most of the stars in IC 1613 are about 7 billion years old, but there are a considerable number of younger stars, as shown in the GALEX image at bottom. Among them are at least five Population II Cepheid variables, which have helped calibrate the period-luminosity relation for Cepheids. Other than the Magellanic Clouds, IC 1613 is the only Local Group irregular galaxy in which the much fainter RR Lyrae variables have also been detected.
SDSS image of irregular galaxy IC 1613
Above, a 12 arcmin region centered on the galaxy
Below, a "deep" image of a slightly smaller field of view
(Image credit and © Jean-Charles Cuillandre (CFHT) & Giovanni Anselmi (Coelum), CFHT; used by permission)
CFHT image of irregular galaxy IC 1613
Below, an ultraviolet image of the 15 arcmin region centered on the galaxy. Low-surface brightness galaxies such as IC 1613 are hard to distinguish from the general background of faint stars in our own galaxy in visible light, but if they contain some hot young stars can be easily observed in the ultraviolet, where the "background" is less noticeable. (Image credit NASA/JPL-Caltech/SSC/GALEX/Planetary Photojournal)
GALEX image of irregular galaxy IC 1613

IC 1614
(= PGC 2025913)

Discovered (Nov 30, 1899) by
Stephane Javelle
A magnitude 16.6 elliptical galaxy (type E0??) in Pisces (RA 01 05 07.0, Dec +33 11 23)
Historical Identification: Per Dreyer, IC 1614 (Javelle #831, 1860 RA 00 57 25, NPD 57 32.5) is "very faint, small, extended 120°, very little brighter middle, 15th magnitude star near."
Note About Designation: Although LEDA has an entry for this galaxy (B 17.6, 0.6 x 0.5 arcmin, 3K 24161 km/sec), it does not recognize it as IC 1614. NED does recognize it as IC 1614, but says very little about it: (17.62 g, 3K Vr 24160 km/sec, z 0.0805886555)
Physical Information: Apparent size 0.3 by 0.3 arcmin?

IC 1615
(= PGC 3812 = ESO 195-027)

Discovered (1899) by
DeLisle Stewart
A magnitude 13.4 spiral galaxy (type Sbc??) in Phoenix (RA 01 04 07.0, Dec -51 07 59)
Historical Identification: Per Dreyer, IC 1615 (DeLisle Stewart #134, 1860 RA 00 57 56, NPD 141 54) is "extremely faint, small, considerably extended 140°, considerably bighter middle."
Physical Information: Apparent size 1.3 by 0.6 arcmin?

IC 1616
(= PGC 3846 = ESO 412-004 = MCG -05-03-022)

Discovered (May 24, 1897) by
Lewis Swift
A magnitude 12.6 spiral galaxy (type SBbc??) in Sculptor (RA 01 04 56.2, Dec -27 25 46)
Historical Identification: Per Dreyer, IC 1616 (Swift list XII (#5), 1860 RA 00 58 04, NPD 118 09.3) is "extremely faint, pretty small, 3 stars in line near."
Physical Information: Apparent size 1.6 by 1.4 arcmin?

IC 1617
(= PGC 3818 = ESO 195-028)

Discovered (1899) by
DeLisle Stewart
A magnitude 13.7 lenticular galaxy (type S0/a??) in Phoenix (RA 01 04 16.8, Dec -51 01 58)
Historical Identification: Per Dreyer, IC 1617 (DeLisle Stewart #135, 1860 RA 00 58 08, NPD 141 47) is "extremely faint, small, considerably extended 130°, considerably brighter middle."
Physical Information: Apparent size 1.4 by 0.6 arcmin?

IC 1618
(= PGC 3899 = UGC 671 = CGCG 501-078)

Discovered (Dec 2, 1896) by
Hermann Kobold
A magnitiude 14.7 lenticular galaxy (type S0??) in Pisces (RA 01 05 56.0, Dec +32 24 44)
Historical Identification: Per Dreyer, IC 1618 (Kobold (#1, K12), 1860 RA 00 58 13, NPD 58 19.1) is "very faint, small."
Physical Information: Apparent size 1.2 by 0.5 arcmin?

Corwin lists a possible companion (PGC 212654) at RA 01 05 50.5, Dec +32 23 19

IC 1619
(= PGC 3975 = CGCG 501-083 = MCG +05-03-054)

Discovered (Nov 28, 1899) by
Stephane Javelle
A magnitiude 14.6 spiral galaxy (type S??) in Pisces (RA 01 07 22.4, Dec +33 04 02)
Historical Identification: Per Dreyer, IC 1619 (Javelle #832, 1860 RA 00 59 41, NPD 57 39.9) is "faint, small, round, gradually brighter middle and faint nucleus., between 2 stars of magnitude 13."
Physical Information: Apparent size 0.7 by 0.5 arcmin?

IC 1620
(= PGC 3960 = UGC 681 = CGCG 435-042 = MCG +02-03-034)

Discovered (Nov 13, 1903) by
Stephane Javelle
A magnitude 13.4 spiral galaxy (type SBbc??) in Pisces (RA 01 07 14.2, Dec +13 57 18)
Historical Identification: Per Dreyer, IC 1620 (Javelle #833, 1860 RA 00 59 51, NPD 76 47.6) is "faint, pretty small, diffuse."
Physical Information: Apparent size 1.0 by 0.7 arcmin?

Corwin lists a possible companion (PGC 3949) at RA 01 07 10.0, Dec +13 57 16

IC 1621
(= PGC 3915 = ESO 243-028)

Discovered (1899) by
DeLisle Stewart
A magnitude 13.2 spiral galaxy (type Sbc??) in Phoenix (RA 01 06 22.7, Dec -46 43 29)
Historical Identification: Per Dreyer, IC 1621 (DeLisle Stewart #136, 1860 RA 01 00 06, NPD 137 28) is "extremely faint, extremely small, much extended 0°, considerably brighter middle."
Physical Information: Apparent size 1.3 by 0.4 arcmin?

IC 1622
(= PGC 3997 = ESO 541-022 = MCG -03-04-001)

Discovered (Nov 19, 1897) by
Lewis Swift
A magnitude 13.7 spiral galaxy (type S??) in Cetus (RA 01 07 36.7, Dec -17 32 19)
Historical Identification: Per Dreyer, IC 1622 (Swift list XI (#11), 1860 RA 01 00 39, NPD 108 15.4) is "very faint, small, round, south-preceding (southwestern) of 2," the other being IC 1623. The position precesses to RA 01 07 32.6, Dec -17 30 27, just over 2 arcmin north-northwest of the galaxy listed above, the description fits and there is nothing nearby except for IC 1623, whose relative position as noted in the description makes the identification certain.
Physical Information: Apparent size 0.7 by 0.5 arcmin?

IC 1623 (=
Arp 236)
(= ESO 541-023 (= PGC 4007 + PGC 4008))
(PGC 4007 = MCG -03-04-003 = "IC 1623A"),
(PGC 4008 = PGC 4009 = MCG -03-04-004 = "IC 1623B")

Discovered (Nov 19, 1897) by Lewis Swift
An interacting pair of galaxies in Cetus (RA 01 07 47.3, Dec -17 30 24)
PGC 4007 = A magnitude 13.9 irregular galaxy (type Irr? pec) at RA 01 07 46.7, Dec -17 30 28
PGC 4008 = A magnitude 14.5 irregular galaxy (type Irr? pec) at RA 01 07 47.6, Dec -17 30 25
Historical Identification: Per Dreyer, IC 1623 (Swift list XI (#12), 1860 RA 01 00 47, NPD 108 13.4) is "bright, considerably small, a little extended, north-following (northeastern) of 2," the other being IC 1622. The position precesses to RA 01 07 40.6, Dec -17 28 27, just under 2.5 arcmin northwest of the interacting galaxies listed above, the description fits and there is nothing nearby except IC 1622, whose relative position as noted in the description makes the identification certain.
Usage By The Arp Atlas: IC 1623 is used by the Arp Atlas an example of a galaxy with the appearance of fission, with the note "Faint outer arm curves around through 270°." Based on the image in the Arp Atlas, Arp must have been referring to the partial spiral arm shown in the wider-field HST images below.
Physical Information: PGC 4008 is a strong infrared radiator (perhaps because part of its light is blocked by dust clouds), while PGC 4007 is a mass of extremely active star-forming regions. For this reason, Corwin lists the positions of several "components" of each galaxy, and PGC 4007 is listed in NED as having strong H II emission (radiation from gases heated by hot, bright young stars).
 The recessional velocity relative to the Cosmic Microwave Background is about 5720 km/sec for PGC 4007, and about 5790 km/sec for PGC 4008. Based on their average recessional velocity of 5755 km/sec (and H0 = 70 km/sec/Mpc), IC 1623 is about 265 to 270 million light-years away. Given that and PGC 4007's apparent size of about 0.55 by 0.45 arcmin and PGC 4008's apparent size of about 0.45 by 0.35 arcmin (from the images below), PGC 4007 is about 40 to 45 thousand light-years across, and PGC 4008 is about 35 thousand light-years across. The overall structure, including the faint outer spiral arm, spans about 1.6 by 1.45 arcmin, or about 125 thousand light-years.
Note About A Small "Galaxy": There is a faint but bluish object, roughly 0.13 by 0.07 arcmin in apparent size, just north of the eastward-streaming northern part of IC 1623's faint outer arm, which is faintly visible in the DSS image (just above the label for IC 1623), and easily visible in the HST images. This object, known only by its coordinates (as GALEXASC J010747.27-172929.1), is a strong UV source, and is undoubtedly a site of rapid star formation (though certainly not as rapid as in its spectacular southern neighbors). Nothing is known about its distance or visible brightness, so whether it is in any way connected with the interacting pair comprising IC 1623 is also unknown; but its apparent position suggests that it is may also be interacting with them, or a cast-off knot of material resulting from their interaction. If a separate galaxy, it would be classified as a nearly irregular spiral (type Sdm?), but its actual nature is unknown. In fact, for all we know, it might be a much closer object that just happens to be in an interesting position.
DSS image of region near irregular galaxies PGC 4007 and PGC 4008, the interacting pair of galaxies that comprise IC 1623, also known as Arp 236; also shown is IC 1622
Above, a 12 arcmin wide DSS image centered on IC 1623, also showing IC 1622
Below, a PanSTARRS image showing the same region
PanSTARRS image of region near irregular galaxies PGC 4007 and PGC 4008, the interacting pair of galaxies that comprise IC 1623, also known as Arp 236; also shown is IC 1622
Below, a 1.25 arcmin wide PanSTARRS image of the interacting pair of galaxies
PanSTARRS image of irregular galaxies PGC 4007 and PGC 4008, the interacting pair of galaxies that comprise IC 1623, also known as Arp 236
Below, a 2 arcmin wide image of IC 1623, showing the faint anti-clockwise "arm"
(Image Credit NASA/ESA/Hubble Heritage (STScI/AURA)-ESA/Hubble Collaboration and A. Evans (U. of Virginia, Charlottesville/NRAO/Stony Brook U.)
HST image of irregular galaxies PGC 4007 and PGC 4008, the interacting pair of galaxies that comprise IC 1623, also known as Arp 236
Below, a 1.75 arcmin wide updated image of IC 1623 also faintly showing the anti-clockwise spiral arm,
and pointing out the nearly irregular spiral 'galaxy' listed as GALEXASC J010747.27-172929.1
(Image Credit ESA/Hubble & NASA, R. Chandar)
HST image of irregular galaxies PGC 4007 and PGC 4008, the interacting pair of galaxies that comprise IC 1623, also known as Arp 236, also faintly showing the anti-clockwise spiral arm, and the nearly irregular spiral 'galaxy' listed as GALEXASC J010747.27-172929.1
Below, a 1 arcmin wide image of the interacting pair (Image Credit as above)
HST image of irregular galaxies PGC 4007 and PGC 4008, the interacting pair of galaxies that comprise IC 1623, also known as Arp 236

IC 1624 (an OCL in the Small Magellanic Cloud)
(= "PGC 3518510")

Discovered (Sep 5, 1826) by
James Dunlop
Discovered (Nov 27, 1900) by DeLisle Stewart
A magnitude 12.9 open cluster in Tucana (RA 01 05 21.8, Dec -72 02 34)
Historical Identification: Per Dreyer. IC 1624 (DeLisle Stewart #137, (Dunlop #34), 1860 RA 01 00 49, NPD 162 47) is "very faint, small, round."
Discovery Note: At the time the IC2 was published, Dunlop's discoveries were not trusted in Europe, unless confirmed by John Herschel in the 1830's. However, it is now felt certain that his #34 was an observation of the open cluster IC 1624, hence the credit given to him above, and the insertion of his observation (in parentheses) in the IC entry.
Note About PGC Designation: For the sake of completeness LEDA assigns PGC designations to many NGC/IC objects that are not galaxies. In this case, a search of the database for that designation does not return a result, hence its being placed in quotes.
Physical Information: Apparent size 0.7 arcmin?

IC 1625
(= PGC 4001 = ESO 243-033)

Discovered (1899) by
DeLisle Stewart
A magnitude 12.0 lenticular galaxy (type E/S0??) in Phoenix (RA 01 07 42.6, Dec -46 54 28)
Historical Identification: Per Dreyer, IC 1625 (DeLisle Stewart #138, 1860 RA 01 01 25, NPD 137 40) is "extremely faint, very small, round, suspected."
Physical Information: Apparent size 1.6 by 1.2 arcmin?

IC 1626 (an OCL in the Small Magellanic Cloud)
(= "PGC 3518511")

Discovered (Nov 27, 1900) by
DeLisle Stewart
An open cluster in Tucana (RA 01 06 13.0, Dec -73 17 54)
Historical Identification: Per Dreyer, IC 1626 (DeLisle Stewart #139, 1860 RA 01 01 59, NPD 164 03) is "very faint, considerably small, round."
Note About PGC Designation: For the sake of completeness LEDA assigns PGC designations to many NGC/IC objects that are not galaxies. In this case, a search of the database for that designation does not return a result, hence its being placed in quotes.
Physical Information:

IC 1627
(= PGC 4027 = PGC 130093 = ESO 243-034)

Discovered (1899) by
DeLisle Stewart
A magnitude 12.9 spiral galaxy (type SBb??) in Phoenix (RA 01 08 10.8, Dec -46 05 38)
Historical Identification: Per Dreyer, IC 1627 (DeLisle Stewart #140, 1860 RA 01 02 01, NPD 137 01) is "considerably faint, small, extremely extended 135°, very much brighter middle."
Physical Information: Apparent size 2.5 by 0.6 arcmin?

IC 1628
(= PGC 4075 = ESO 412-007 = MCG -05-03-027)

Discovered (Oct 12, 1897) by
Lewis Swift
A magnitude 12.5 lenticular galaxy (type E/S0? pec) in Sculptor (RA 01 08 47.5, Dec -28 34 56)
Historical Identification: Per Dreyer, IC 1628 (Swift list XII (#6), 1860 RA 01 02 05, NPD 119 19.4) is "considerably bright, pretty small, round, 3 stars of magnitude 8 near."
Physical Information: Apparent size 1.1 by 1.1 arcmin?

Corwin lists a possible companion (PGC 4083) at RA 01 08 50.7, Dec -28 35 57

IC 1629
(= PGC 4122 = CGCG 385-009)

Discovered (Dec 22, 1897) by
Stephane Javelle
A magnitude 14.4 "compact" galaxy (type C??) in Cetus (RA 01 09 18.2, Dec +02 34 03)
Historical Identification: Per Dreyer, IC 1629 (Javelle #834, 1860 RA 01 02 06, NPD 88 10.9) is "faint, very small, round, stellar."
Physical Information: Apparent size 0.4 by 0.3 arcmin?

IC 1630
(= PGC 4036 = ESO 243-036)

Discovered (1899) by
DeLisle Stewart
A magnitude 14.3 spiral galaxy (type Sb??) in Phoenix (RA 01 08 16.7, Dec -46 45 14)
Historical Identification: Per Dreyer, IC 1630 (DeLisle Stewart #141, 1860 RA 01 02 07, NPD 137 31) is "extremely faint, extremely small, extended 60°, suspected."
Physical Information: Apparent size 1.5 by 0.3 arcmin?

IC 1631
(= PGC 4068 = ESO 243-040)

Discovered (1899) by
DeLisle Stewart
A magnitude 13.3 spiral galaxy (type Sab??) in Phoenix (RA 01 08 44.8, Dec -46 28 32)
Historical Identification: Per Dreyer, IC 1631 (DeLisle Stewart #142, 1860 RA 01 02 31, NPD 137 13) is "extremely faint, small, round, suspected."
Physical Information: Apparent size 0.9 by 0.6 arcmin?

IC 1632
(= PGC 4205)

Discovered (Dec 23, 1897) by
Stephane Javelle
A magnitude 15.5 elliptical galaxy (type E0??) in Pisces (RA 01 10 43.4, Dec +17 41 00)
Historical Identification: Per Dreyer, IC 1632 (Javelle #835, 1860 RA 01 03 16, NPD 73 04.2) is "very faint, very small, diffuse, 15th magnitude star very close."
Physical Information: Apparent size 0.2 by 0.2 arcmin?

Corwin lists a possible companion (a star?) at RA 01 10 42.5, Dec +17 40 51

IC 1633
(= PGC 4149 = ESO 243-046)

Discovered (Aug 5, 1826) by
James Dunlop
Discovered (Sep 29, 1897) by Lewis Swift
Discovered (1899) by DeLisle Stewart
A magnitude 11.5 elliptical galaxy (type E1??) in Phoenix (RA 01 09 55.5, Dec -45 55 52)
Historical Identification: Per Dreyer, IC 1633 (Swift list XI (#?), DeLisle Stewart (#?), (Dunlop #437), 1860 RA 01 03 31, NPD 136 42.7) is "very faint, small, round, very faint star following (to east)."
Discovery Note: At the time the IC2 was published, Dunlop's discoveries were not trusted in Europe, unless confirmed by John Herschel in the 1830's. However, it is now felt certain that his #437 was an observation of what became IC 1633, hence the credit given to him above, and the insertion of his observation (in parentheses) in the IC entry.
Physical Information: Apparent size 2.6 by 2.4 arcmin?

IC 1634
(= PGC 4232 = UGC 740 = CGCG 459-014 = MCG +03 -04-008)

Discovered (Dec 23, 1897) by
Stephane Javelle
A magnitude 14.7 elliptical galaxy (type E0??) in Pisces (RA 01 11 02.9, Dec +17 39 46)
Historical Identification: Per Dreyer, IC 1634 (Javelle #836, 1860 RA 01 03 36, NPD 73 05.4) is "faint, small, round, gradually brighter middle, mottled but not resolved."
Physical Information: Apparent size 0.4 by 0.4 arcmin?

IC 1635
(= PGC 4231 = UGC 739 = CGCG 459-013 = MCG +03-04-009)

Discovered (Dec 23, 1897) by
Stephane Javelle
A magnitude 14.7 elliptical galaxy (type E0??) in Pisces (RA 01 11 03.5, Dec +17 39 07)
Historical Identification: Per Dreyer, IC 1635 (Javelle #837, 1860 RA 01 03 37, NPD 73 06.1) is "faint, small, round, gradually brighter middle, mottled but not resolved."
Physical Information: Apparent size 0.3 by 0.3 arcmin?

IC 1636
(= PGC 4280 = CGCG 501-125 = CGCG 502-001)

Discovered (Oct 17, 1903) by
Stephane Javelle
A magnitude 14.4 lenticular galaxy (type S0??) in Pisces (RA 01 11 37.5, Dec +33 21 16)
Historical Identification: Per Dreyer, IC 1636 (Javelle #838, 1860 RA 01 03 51, NPD 57 23.4) is "faint, very small, gradually brighter middle and nucleus."
Physical Information: Apparent size 0.3 by 0.2 arcmin?

IC 1637
(= PGC 4227 = ESO 412-010 = MCG -05-04-003)

Discovered (1899) by
DeLisle Stewart
A magnitude 12.8 spiral galaxy (type SBc??) in Sculptor (RA 01 11 01.1, Dec -30 26 18)
Historical Identification: Per Dreyer, IC 1637 (DeLisle Stewart #144, 1860 RA 01 04 24, NPD 121 11) is "extremely faint, small, round, suspected."
Physical Information: Apparent size 1.7 by 1.3 arcmin?

IC 1638
(= PGC 4338 = CGCG 501-129 = CGCG 502-005 = MCG +05-03-082)

Discovered (Oct 17, 1903) by
Stephane Javelle
A magnitude 14.1 lenticular galaxy (type S0??) in Pisces (RA 01 12 21.8, Dec +33 21 52)
Historical Identification: Per Dreyer, IC 1638 (Javelle #839, 1860 RA 01 04 35, NPD 57 22.8) is "faint, very small, round, gradually brighter middle and nucleus, mottled but not resolved."
Physical Information: Apparent size 0.7 by 0.7 arcmin?

IC 1639
(= PGC 4292 = UGC 750 = CGCG 385-023 = MCG +00-04-031)

Discovered (Dec 14, 1903) by
Stephane Javelle
A magnitude 13.1 peculiar galaxy (type pec??) in Cetus (RA 01 11 46.6, Dec -00 39 52)
Historical Identification: Per Dreyer, IC 1639 (Javelle #840, 1860 RA 01 04 36, NPD 91 25.0) is "very small, round, stellar."
Physical Information: Apparent size 0.9 by 0.8 arcmin?

IC 1640
(= PGC 4299 = CGCG 385-024)

Discovered (Dec 14, 1903) by
Stephane Javelle
A magnitude 14.4 "compact" galaxy (type C??) in Cetus (RA 01 11 51.3, Dec -00 37 49)
Historical Identification: Per Dreyer, IC 1640 (Javelle #841, 1860 RA 01 04 41, NPD 91 23.0) is "very small, round, brighter middle and nucleus."
Physical Information: Apparent size 0.2 by 0.2 arcmin?

IC 1641
(an OCL in the Small Magellanic Cloud)
(= "PGC 3518512")

Discovered (Nov 27, 1900) by
DeLisle Stewart
An open cluster in Tucana (RA 01 09 39.1, Dec -71 46 08)
Corwin's position is RA 01 09 25.1, Dec -71 46 02; is that the same cluster?
Historical Identification: Per Dreyer, IC 1641 (DeLisle Stewart #143, 1860 RA 01 04 56, NPD 162 31) is "extremely faint, extremely small, round."
Note About PGC Designation: For the sake of completeness LEDA assigns PGC designations to many NGC/IC objects that are not galaxies. In this case, a search of the database for that designation does not return a result, hence its being placed in quotes.
Physical Information:

IC 1642 (=
IC 1645)
( = PGC 95507 = CGCG 436-009 = MCG +02-04-008)

Discovered (Jan 29, 1897) by Stephane Javelle (and later listed as IC 1642)
Discovered (Nov 24, 1897) by Stephane Javelle (and later listed as IC 1645)
A magnitude 15.5 lenticular galaxy (type E/S0??) in Pisces (RA 01 12 27.3, Dec +15 45 00)
Historical Identification: Per Dreyer, IC 1642 (Javelle #842, 1860 RA 01 04 57, NPD 74 59.2) is "faint, small, round, a little brighter middle and nucleus."
Physical Information: This entry will only contain historical information; for anything else see IC 1645.

IC 1643
(= PGC 4328 = CGCG 385-025 = MCG +00-04-033)

Discovered (Dec 18, 1897) by
Stephane Javelle
A magnitude 14.2 spiral galaxy (type S??) in Cetus (RA 01 12 08.6, Dec -00 24 37)
Historical Identification: Per Dreyer, IC 1643 (Javelle #843, 1860 RA 01 05 00, NPD 91 10.0) is "faint, small, round, gradually brighter middle."
Physical Information: Apparent size 0.8 by 0.8 arcmin?

IC 1644 (an OCL in the Small Magellanic Cloud)
(= "PGC 3518575")

Discovered (1901) by
Williamina Fleming
An emission nebula in Tucana (RA 01 09 13.0, Dec -73 11 38)
Historical Identification: Per Dreyer, IC 1644 (Fleming #83, 1860 RA 01 05 02, NPD 163 57) is "planetary, stellar."
Note About PGC Designation: For the sake of completeness LEDA assigns PGC designations to many NGC/IC objects that are not galaxies. In this case, a search of the database for that designation does not return a result, hence its being placed in quotes.
Physical Information:

IC 1645 (=
IC 1642
( = PGC 95507 = CGCG 436-009 = MCG +02-04-008)

Discovered (Jan 29, 1897) by Stephane Javelle (and later listed as IC 1642)
Discovered (Nov 24, 1897) by Stephane Javelle (and later listed as IC 1645)
A magnitude 15.5 lenticular galaxy (type E/S0??) in Pisces (RA 01 12 27.3, Dec +15 45 00)
Historical Identification: Per Dreyer, IC 1645 (Javelle #844, 1860 RA 01 05 03, NPD 75 00.2) is "faint, small, round, diffuse."
Physical Information: Apparent size 0.4 by 0.4 arcmin?

IC 1646
(= PGC 4357 = PGC 1491410 = CGCG 436-010 = MCG +02-04-009)

Discovered (Nov 24, 1897) by
Stephane Javelle
A magnitude 14.5 spiral galaxy (type SBbc??) in Pisces (RA 01 12 43.8, Dec +15 42 28)
Historical Identification: Per Dreyer, IC 1646 (Javelle #845, 1860 RA 01 05 20, NPD 75 02.8) is "very faint, pretty small, diffuse."
Physical Information: Apparent size 0.5 by 0.5 arcmin?

Corwin lists a possible companion () or (probably) knot at RA 01 12 44.3, Dec +15 42 16

IC 1647
(= PGC 4390 = CGCG 520-027 = MCG +06-03-024)

Discovered (Nov 12, 1903) by
Stephane Javelle
A magnitude 15.0 spiral galaxy (type Sc??) in Andromeda (RA 01 13 14.6, Dec +38 53 08)
Historical Identification: Per Dreyer, IC 1647 (Javelle #846, 1860 RA 01 05 22, NPD 51 51.8) is "very faint, small, round, difficult."
Physical Information: Apparent size 0.7 by 0.3 arcmin?

IC 1648
(= PGC 4417 = GCG 501-131 = CGCG 502-007)

Discovered (Dec 7, 1899) by
Stephane Javelle
A magnitude 14.4 lenticular galaxy (type S0??) in Pisces (RA 01 13 42.1, Dec +33 13 05)
Historical Identification: Per Dreyer, IC 1648 (Javelle #847, 1860 RA 01 05 55, NPD 57 31.5) is "faint, very small, round, nuclear, mottled but not resolved."
Physical Information: Apparent size 0.4 by 0.3 arcmin?

IC 1649
(= PGC 4298 = ESO 151-030)

Discovered (1899) by
DeLisle Stewart
A magnitude 13.9 spiral galaxy (type Sbc??) in Phoenix (RA 01 11 50.9, Dec -55 51 26)
Historical Identification: Per Dreyer, IC 1649 (DeLisle Stewart #145, 1860 RA 01 06 08, NPD 146 37) is "extremely faint, considerably small, extended 140°, considerably brighter middle."
Physical Information: Apparent size 1.7 by 0.3 arcmin?
Celestial Atlas
(IC 1550 - 1599) ←IC Objects: IC 1600 - 1649→ (IC 1650 - 1699)