Date and Time of the Query: 2019-05-20 T04:55:03 PDT
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Notes for object NGC 1398

12 note(s) found in NED.

1. 2004A&A...415..941E
Re:NGC 1398
NGC 1398 (inner disk): Erwin et al. (2004), based partly on
Jungwiert et al. (1997). The inner "triaxial bulge" identified by
Jungwiert et al. (see also Wozniak et al. 1995), with a_{epsilon}_
~13", appears to be a large stellar nuclear ring; the inner disk
listed here shows up in HST images. Bar measurements are from the
ellipse fits of Wozniak et al. (1995) and Jungwiert et al. (1997);
inner-disk measurements are from WFPC2 F606W and F814W images.
Outer-disk inclination and PA are from H I kinematics (Moore &
Gottesman 1995).

2. 2003ApJS..146..353M
Re:NGC 1398
NGC 1398 (N)
There is no dust structure at all, and even the color map is extremely
constant. The nucleus is only barely visible as a slightly bluer point
on the otherwise flat color map.

3. 2002AJ....123..159C
Re:NGC 1398
Center is blue; blue feature ~4" southeast of center

4. 1997A&AS..125..479J
Re:NGC 1398
NGC 1398 (R'SBab, 1"~80 pc, I=48.0^deg^)
The disk is dominated by a well defined large-scale bar reaching e_max_(0.37)
at a=36" after which it passes into an outer ring. The inner isophotes (a<20",
PA~80-90^deg^) are not aligned with the primary bar (PA^P^~12^deg^) and are
slightly twisted (by ~13^deg^ between 5 and 12"). A small bump in profiles near
a=14" was found also by W95 but they were reluctant to interpret it. We
consider it is related to the triaxiality of the bulge; its signature is seen
also in deprojected profiles (PA_disk_=100^deg^). Note that the inner isophote
twist almost disappears after deprojection: the PA is constant (within 75^deg^)
along the whole 60"-profile.

5. 1994CAG1..B...0000S
Re:NGC 1398
Hubble Atlas, p. 47
Oct 25/26, 1981
103aO + GG385
45 min
The bar across the central lens is burned out on the heavily
printed image here but is well seen in the negative print on the next
The photographic contrast of the print here has been adjusted to
emphasize the thin fragments of arms in the outer disk. The two main
arms that emerge from the rim of the bright inner disk (the connection
is seen best on the next panel) branch into a multitude of secondary
fragments which themselves are thin and in which HII regions are
abundant. The main arm emerges from the rim of the lens at the
position angle of about 6 o'clock. It can be traced as a coherent
fragment for a wrap of about 270 deg. The opposite arm can be traced
for only about 200 deg. Secondary branches begin to occur after about
one-fourth of a revolution in both arms.

6. 1994CAG1..B...0000S
Re:NGC 1398
Hubble Atlas, p. 47
Oct 25/26, 1981
103aO + GG385
45 min
The prominent bar ends at the rim of the high-surface-brightness
inner disk. (There is no actual "rim" but rather a sharp change in the
gradient of the disk surface brightness, which appears to the eye as
the edge of the inner disk, also well seen on the preceding panel.)
The inner arms that form a near-ring are very tightly wound at
the rim of the disk. It is here that the two main arms emerge which
will fragment into the MAS pattern farther out. Each begins in the
outer region of the lens at diametrically opposite points about 90 deg
from the termination points of the bar on the edge of the lens, a
feature seen and often described in the SBa section.
The thinness of the well-defined arms, the tightness of the
spiral pattern, and the size of the central smooth (non-star-forming)
region require the SBab classification. The type in the Hubble Atlas
is SBb. NGC 1398 is clearly among the earliest of the SBb galaxies in
that atlas. The SBb morphological box is divided here into SBab types
at the early part, and SBbc at the latest part of that box.

7. 1993ApJS...88..415R
Re:NGC 1398
As described in Sandage (1961), this is the prototypical example of a
SB(r)b, with spiral arms starting tangent to an external ring, itself
made up from spiral segments. The H II regions are tightly confined to
the inner and outer rings. The inner ring appears to consist of two arms
that wrap around some 270^deg^ each and spiral inward, while the outer
arms cover only 180^deg^ and do not quite wrap tightly enough to close in
on each other. The morphology of these types of outer rings and
pseudorings, and their possible associations with the Lindblad resonances
are discussed in a recent paper by Buta & Crocker (1991).

8. 1985SGC...C...0000C
Re:NGC 1398
Plate 3620
Overexposed center and bar, bright knotty (r): 1.6 x 1.4; thin knotty
arms form (R'): 4.6 x 3.2.

9. 1982ESOU..C...0000L
Re:ESO 033645-2629.9
=ESO 482- G 22
in cluster

10. 1976RC2...C...0000d
Re:NGC 1398
Description and Classification:
P.A.S.P., 81, 51, 1969.
J.R.A.S. Canada, 68, 117, 1974.

11. 1964RC1...C...0000d
Re:NGC 1398
Large, bright nucleus
in a narrow bar: 1.2 arcmin x 0.2 arcmin.
(r): 1.6 arcmin x 1.3 arcmin.
2 main, narrow, partially resolved, branching arms.
Pseudo (R): 4.8 arcmin x 3.3 arcmin.
Ap. J., 92, 236, 1940.
P.A.S.P., 59, 309, 1947.
Ap. J., 135, 697, 1961.

12. 1961Hubbl.B...0000S
Re:NGC 1398
Oct. 25/26, 1952
103aO + WG2
30 min
Enlarged 4.0X
This is the type example of the SBb(r). Note how the
spiral arms start tangent to an external "ring." The ring
is not complete but is composed of nearly circular spiral
segments. The faint external arms are difficult to trace
as continuous bands. They tend to break into segments.
Neglecting the slight discontinuities, the two principal
arms can be traced for about one and a quarter revolutions
from their origin on the internal "ring."
There are no straight absorption lanes in the bar, as is
characteristic of the NGC 1300 type of SBb.

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