U 421
04:30 to 05:30
-39° to -50°
Ret, Dor, Pic
Nov-Mar

FEATURED OBJECTS: NGC 1617, Reticulum 1, NGC 1672, NGC 1688, NGC 1705.

NGC 1617
ESO157-G041
RA 04:31:38
Dec -54°36.1'
Galaxy

h: "pB, L, mE, sbM, 3' long, 2' broad, pos. 105.8 degrees." On a second occassion he called it "B, L, mE, frist very gradually then very suddenly much brighter to the middle to a nucleus 5 arcseconds in diameter; 3' long, 1' broad." Herschel notes that this object could be Dunlop 339, which was observed by James Dunlop as "a small round pretty well defined nebula, bright in the centre, N.p. Alpha Doradus."

Gerd Bahr-Vollrath (Noosa Heads, Queensland, Australia) writes in the The Webb Society Nebulae and Clusters Section Report No. 11, January 1993: "A fairly large and bright spindle with a prominent, almost stellar nucleus. No other structure visible. (8-inch f/12 SCT)"

ASV Journal Vol 24 No 3 June 1971: "just visible in 3-inch."

Sandage (1975, Astrophysical Journal, 202, 563-582) notes that this galaxy is a member of the Dorado Group. Members include NGC 1515, NGC 1533, NGC 1536, NGC 1543, NGC 1546, NGC 1553, NGC 1566, NGC 1574, NGC 1596, NGC 1617 and IC 2056. Possible additional members include NGC 1559, NGC 1602, NGC 1672, NGC 1688, NGC 1703 & NGC 1705
G. de Vaucouleurs ("Galaxies and the Universe", Chapter 14 - Nearby Groups of Galaxies) notes that the five brightest members of the NGC 1566 group, a part of the Dorado Cloud complex, are NGC 1566, NGC 1553, NGC 1549, NGC 1617 & NGC 1574.
Shobbrook (1966, Mon. Not. R. astr. Soc., Vol 131, p351-363) notes that this member of the Dorado Cluster has V = 10.73, B-V = 0.93 and U-B = 0.45. It measures 3.0 by 1.6.

11x80: (exurban skies, seeing 6, transparency 7, darkness 7, lim mag = 6.0 naked eye, pole) “Not seen. Several small stars seen, not shown on the Uranometrias, but no definite galaxy.” (exurban skies, seeing 6, transparency 7, darkness 7, lim mag = 6.0 naked eye, pole, very strong SE wind )” “Very perhaps imagined on two occassions; stars fainter than 9 seen.” (suburban skies) [AS]

12-inch Meade, 53’ fov: Small, faint, round, very bright starlike nucleus surrounded in haziness. Few dim stars in the field. (suburban skies) [MS]

15.5-inch f/9 Newtonian: At 220x, this galaxy has a small nucleus, elongated west-east. The nucleus is sudden. Most of the nebulosity lies to the north of this nucleus. The brightest part of the nucleus is oval in shape. (suburban skies) [AS]

Reticulum 1
ESO118-G031, Se 40/3
RA 04:36:12
Dec -58°51.1'
Globular cluster

See Sky & Telescope, April 1976, p 246

NGC 1672
ESO118-G043
RA 04:45:42
Dec -59°15.0'
Galaxy

h: "B, L, pmE, svmbM to a nucleus; 2.5' long, 1.5' broad; a star 12th mag involved." On a second occassion he called it "B, L, mE, first gradually then psmbM, 4' long, 1,5' broad."

This object is possibly Dunlop 296: ("a faint ill-defined nebula, with a small bright point in the preceding side, which I suspect to be a star; there are several similar small stars in the field.")

Hartung notes: “only the brighter central region is visible with 30cm as a fairly bright haze 3’ x 2’ in pa 60 deg, with a well-defined small nucleus. 15cm shows the general form but it is only a faint hazy spot with 10.5cm.”

ASV Journal Vol 24 No 3 June 1971: "perceptible in 3-inch."

Sandage (1975, Astrophysical Journal, 202, 563-582) notes that this galaxy is a member of the Dorado Group. Members include NGC 1515, NGC 1533, NGC 1536, NGC 1543, NGC 1546, NGC 1553, NGC 1566, NGC 1574, NGC 1596, NGC 1617 and IC 2056. Possible additional members include NGC 1559, NGC 1602, NGC 1672, NGC 1688, NGC 1703 & NGC 1705
G. de Vaucouleurs ("Galaxies and the Universe", Chapter 14 - Nearby Groups of Galaxies) notes that the five brightest members of the NGC 1672 Group, a part of the Dorado Cloud complex, are NGC 1559, NGC 1672, NGC 1688, NGC 1796 & NGC 1703.

11x80: “Stonesthrow north of kappa Dor. Readily seen as an irregularly round glow, within a narrow triangle of 9.5 magnitude stars. About 45 arcseconds across.” On a second occasion: “Found while sweeping, confirmed on starmap. Third of three in a short curve, other two being stars. Small, round nebulous glow, distinctly seen with averted vision.” (exurban seeing 6, transparency 7, darkness 7, lim mag = 6.0 naked eye, pole) [AS]

8-inch Meade, 53’ fov: Small, fairly bright, uneven roundish galaxy with a bright central region in a star rich field. [MS]

NGC 1688
ESO119-G006
RA 04:48:23
Dec -59°48.0'
Galaxy

h: "B, R, first gradually then pslbM, 1'." On a second occassion he called it "vF, pL, R, gbM, 50 arcseconds." His third observation was recorded as "pB, irregularly round, pgmbM, 1'."

NGC 1705
ESO158-G013
RA 04:54:12
Dec -53°21.7'
Galaxy

h: "B, S, R, pmbM, 20 arcseconds." On a second occassion he called it "pB, S, R, gpmbM, 15 arcseconds." His third observation was recorded as "vF, S, R, psbM, 20 arcseconds, very dilute at the borders."

Other names: “E158-13”. Inclination: (face-on, in degrees) 49 Total photoelectric blue mag 12.77 Total colour index .38 Logarithm of the angular diameter D25 (arcminutes) 1.28 Blue photographic magnitude 12.80 This galaxy is included in a sample of galaxies with velocity less than 500km/s with respect to the centroid of the Local Group. [Nearby Galaxies. Schmidt K.-H., Priebe A., Boller T. (Astron. Nachr. 314, 371 (1993))]