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Date and Time of the Query: 2019-03-25 T17:39:04 PDT
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Notes for object NGC 1232A

5 note(s) found in NED.


1. 1994CAG1..B...0000S
Re:NGC 1232A
[Pair with] NGC 1232
Hubble Atlas, p. 32
SBmIII
CD-679-Br
Jan 26/27, 1979
103aO + GG385
45 min
NGC 1232 is one of the wonders in the sky.
It is the prototype of a highly regular
multiple-armed spiral of the earliest luminosity
class.
The arms start at the edge of a
high-surface-brightness disk. Only two major arms
begin at this rim. After about one-quarter
revolution, each branches into two fragments which
after further unwinding branch again until a highly
multiple armed structure spreads over the outer
disk.
Each fragment is well separated from the
others; the geometrical entropy of the pattern is
as low as in any galaxy in the RSA, equal or
somewhat lower than in other highly regular Sc
galaxies such as NGC 309 (Hubble Atlas, p. 32;
panel 221 here) and NGC 5364 (Hubble Atlas,
p. 32; panel 217 here).
The arms are filled with HII regions and
candidates for brightest stars. The largest HII
regions have core + halo diameters of 3". The
redshift is v_o = 1775 km/s.
The SBmIII companion to the east is
separated from NGC 1232 by 4.0'. There is
confusion (c. 1992) as to whether this highly
resolved galaxy is at the same distance as
NGC 1232. The redshift of NGC 1232A measured by
Welch, Chincarini, and Rood (1975) of
v_o = 1780 km/s was rejected by de Vaucouleurs,
de Vaucouleurs, and Nieto (1979) in favor of
v_o = 6496 km/s measured by them from an H{alpha}
line. However, a 21-cm HI redshift of v_o = 1772
km/s by Reif, Mebold, Goss, van Woerden, and
Siegman (1982) confirmed the early value by
Welch et al. But an even later 21-cm redshift
confirms the larger redshift near v_o = 6500 km/s.
The resolution of NGC 1232A into stars
and HII regions at the same level as in NGC 1232
itself makes no sense in the conventional
interpretation of redshifts as a precise distance
indicator if the high redshift value is correct. The
case remains an important mystery (c. 1992).
At the mean redshift distance of 35 Mpc, the
projected linear separation of NGC 1232A from
NGC 1232 is small at 41 kpc if they are at the
same distance. If not, the mystery remains.

2. 1985SGC...C...0000C
Re:NGC 1232A
Plate 3749
Overexposed center and bar, dist knotty arms. 4.0 south-following-following
NGC 1232.

3. 1982ESOU..C...0000L
Re:ESO 030747-2047.3
=ESO 547- G 16
included in ESO 547- G 14
*=Arp 41
*=NGC 1232 A

4. 1976RC2...C...0000d
Re:NGC 1232A
Dwarf SB(s)m satellite at 4.0 arcmin following NGC 1232.

5. 1964RC1...C...0000d
Re:NGC 1232A
= No. 212 in Lund 7 (0.7 arcmin x 0.5 arcmin).
At 4.0 arcmin from NGC 1232.
Bright bar: 0.3 arcmin x 0.08 arcmin
with asymmetric loop: 0.8 arcmin x 0.75 arcmin.
Typical dwarf SB(s)m system.


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