ULX1 and ULX2 are both close to knots on the dusty spiral arms of this Scd
spiral galaxy at a distance of 13.6 Mpc.
NGC 1559.---SBcd (see Fig. 4e): Moderately inclined. Elliptical
nucleus extends into short, high surface brightness bar. Bar is
thicker in the middle than at the ends. This is the only sign of a
bulge. Flocculent spiral pattern, with evidence for at least three
patchy arms. Arms are rich in star-forming knots. At low surface
brightness levels there are a number of wispy extensions of the arms.
In Figure 4e, note the patches of strong dust absorption that appear
as red (H-band emission only) interspersed with the bright blue
knots. The disk is much smoother in the H band than the optical.
NGC 1559 (Fig. 19) possesses massive spiral arms with strong star
formation. The small bar of about 40" length is oriented almost east-west.
Very strong radio emission originates in the bar and the disc. Polarized
emission is strongly asymmetric with peaks near the ends of the bar and
magnetic field lines at large angles to the bar (Fig. 26). The region
where the magnetic field is strongly aligned and almost perpendicular to
the bar's major axis is larger than in NGC 1097.
NGC 1559. - We adopt the SN II expanding photosphere distance from
Eastman et al. (1996).
Pair? [with IC 2056]
Jan 1/2, 1981
103aO + GG385
NGC 1559 is in the complex Dorado region.
It is located about 6^deg^ south of the center of the
dense Dorado Group (de Vaucouleurs 1975, No. G16)
and has about the same redshift. Ferguson
and Sandage (1990) list
the mean redshift of the Group. The redshift of
NGC 1559 is v_o = 1093 km/s.
NGC 1559 may form a wide physical pair
with IC 2056 (Sc; panel 253) at a separation of
2.6^deg^. The redshift of IC 2056 is v_o = 934 km/s.
At the mean redshift distance of 20 Mpc (H = 50)
the projected linear separation is 909 kpc,
somewhat larger than the distance from our Galaxy
to M31 in the Local Group.
HII regions exist throughout the spiral
pattern in NGC 1559. The largest are complex, with
halo diameters of about 6". Individual stars
appear to resolve out of the background at about
B = 22.
Overexposed center, overexposed patchy arms with many very bright knots.
Very high-surface-brightness arms with many lumps.
Candidate for HII resolution studies.
M.N.R.A.S., 131, 351, 1966.
Atlas Gal. Austr., 1968.
Australian J. Phys., 19, 883, 1966.
Short, bright bar.
Bright arms with knots.
High surface brightness.
P.N.A.S., 26, 34, 1940.