Hickson 17

 

Hickson 17, galaxy group, Cetus. All members in PGC. 2021-11-05. Cherry Springs, transp. 8/10, seeing 0.5-1 arcsec, sky 21.3-21.5 mag/arcsec2. Telescope: D = 508 mm, F/4. Oculars: 8 mm (250x). Component A and two unequal stars visible NW of a brighter field star. B vaguely glimpsed. At 360x, the group appears overmagnified.

Hickson 15

 

Hickson 15, galaxy group, Cetus. Members A-D in UGC, E and F in MCG. 2021-11-05, Cherry Springs, transp. 8/10, seeing 0.5-1 arcsec, sky 21.3-21.5 mag/arcsec2. Telescope: D = 508 mm, F/4. Ocular: 8 mm (250x). A, B, C, D fairly bright, compact. E fainter. F at the threshold, in a tight group with D and a star.

Hickson 14

 

Hickson 14, galaxy group, Cetus. All members in MCG. 2021-11-05, Cherry Springs, transp. 8/10, seeing 0.5-1 arcsec, sky 21.3-21.5 mag/arcsec2. Telescope: D = 508 mm, F/4. Ocular: 8 mm (250x). Component A elongated, B slightly elongated, C small, D small, very faint, diffuse.

Hickson 99

 

Hickson 99, galaxy group, Peg. Members in the MCG, UGC, PGC. 2021-10-01, Spruce Knob, 4800 ft. Clear, calm, dry. Transp. 7/10, seeing 1", SQM 21.4-21.6. Telescope: 20-inch F/4. Ocular: 8 mm (250x). Component A greatly elongated NS, bright star just SW of its S end. A somewhat brighter, small core. Component B round, concentrated. C immediately to its W, almost stellar core, E and W ends enhanced. D and E very small, featureless. Stars NNE and ESE of B have USNOA2 Vm 15.35 and 16.55. Sketch on black paper, finished at the telescope.

SDSS

Hickson 97

 

Hickson 97, galaxy group, Psc. Components A-D are in the IC, E is PGC. 2021-10-01, Spruce Knob, 4800 ft. Clear, calm, dry. Transp. 7/10, seeing 1", SQM 21.4-21.6. Telescope: 20-inch F/4. Ocular: 8 mm (250x). Component A the larges, has a bright core, elongated NNW-SSE. Component E to the NW of it, small, diffuse. Two stars W of component E are USNOA2 Vm 16.4 and 17. Component D is immediately N of a fairly bright star, touching it. C elongated NE-SW with a small bright core. B is a thin edge-on with a small flat core. Sketch on black paper, finished at the telescope.

SDSS

Hickson 90

 

Hickson 90, galaxy group, PsA. All members in the NGC. 2021-10-01, Spruce Knob, 4800 ft. Clear, calm, dry. Transp. 7/10, seeing 1". SQM 21.4-21.6. Telescope: 20-inch F/4. Ocular: 8 mm (250x). Component A (NGC 7172) displays a small core and asymmetrical extensions flanking a strong equatorial dust lane, longer to the E. B compact, bright. C appears as an off-center, diffuse extension of B toward the W. D is small, round, slightly concentrated. 3 stars to the E of the group, 2 to the W.

DSS

Hickson 89

Hickson 89, galaxy group, Aqr. All members are in the PGC. 2021-10-01, Spruce Knob, summit, 4800 ft. Clear, calm, dry. Transp. 7/10, seeing 1". SQM 21.4. Telescope: 20-inch F/4. Ocular: 8 mm (250x). Component A round, slightly concentrated, largest. Component B smaller. C and D almost touch, an unequal pair. Bright star W of A, fainter star NE of B. 4 faint stars stretch S of the group, of which the one S of the line between B and C-D has a very faint companion immediately to the N (USNOA2 Vm 15.5). Sketch on black paper, finished at the telescope.

SDSS

My Arp Article in Sky and Telescope

 

Sky and Telescope (October 2021, p. 57-59) has published my article on peculiar galaxies that is based on the material that first appeared in this blog.

Abell 33

Abell 33 (PN, Hya). Aperture 20", F/4. Ocular 13 mm, OIII filter. Cherry Springs, April 2, 2021. Transp. 9/10, seeing 2 arcsec, SQM 21.88. Large, somewhat mottled annulus, W side brighter. Greenish. Bright star on SW edge, close star pair on NW edge, fainter star close to the pair's NE, faint star on E edge.

PANSTARRS zg

Abell 21

Abell 21 (PK 205+14.1), Gem. February 3, 2021. Beaver Meadow [500 m a.s.l.]. 20" F/5. Clear, transp. 8/10, seeing > 4 arcsec, SQM 20.7 (snow). Not visible in 26 mm without a filter. Obvious with OIII. Crescent-shaped; extended overall NE-SW with enhanced ends, convex to the E. A star is embedded in the N part. A filament separates on the E side, running S to a star. In 13 mm with OIII, the SW end appears separated and has two extensions, to the W and E.

PANSTARRS g

Hickson 33

Elevation 550 m, telescope D = 0.5 m, F = 2.5 m. Sky 20.5 mag/sq arcsec, seeing > 4 arcsec. Hickson 33, galaxy group, Tau. February 3, 2021. Visible already in a 26 mm ocular as a mottled patch with some stars. In 5.5 mm, components A and B are readily seen, round, smoothly concentrated, with diffuse edges. Component D is a hazy companion of a star. C not visible. Unequal double star NE of D resolved, touching [Vm 16-17, 5" sep.].

Hickson 36

Elevation 550 m, telescope D = 508 mm, F = 2500 mm. Sky 20.8 mag/sq arcsec, seeing 4 arcsec. Hickson 36, galaxy group, Cnr. Component A (IC 528) is readily visible in a 13 mm ocular next to a bright star, elongated NNW-SSE. In 5.5 mm, component D is easily seen, elongated WNW-ESE. B and C are difficult but eventually can be seen simultaneously. The close companion of the star to the SW of the group and a similarly faint star to the NNW are seen [interpolated Vm 15.1, 15.2 by USNOA2].