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Date and Time of the Query: 2019-06-15 T18:02:13 PDT
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Notes for object NGC 1705

12 note(s) found in NED.


1. 2009ApJ...705..962C
Re:NGC 1705
This sight line intercepts HVC WW487, which is seen centered at V_LSR_ ~
285 km s^-1^ in both H I data (Wakker & van Woerden 1991) and in multiple
absorption lines in the STIS bandpass (Vazquez et al. 2004). The Si III profile
shows the WW487 feature and a positive velocity HVC that extends over V_LSR_ =
100 to 148 km s^-1^. The lower-velocity HVC is seen in lines of Si II and C II
as well. High-velocity O VI associated with both features was detected by S03.
The prominent feature at V_LSR_ > 400 km s^-1^ is Si III absorption intrinsic to
NGC 1705.

2. 2008MNRAS.385..553D
Re:NGC 1705
NGC 1705: This peculiar galaxy shows a rotating disc that is dominated
by an intense ongoing starburst. Therefore, no kinematical parameters
could be extracted. The double profiles and multiple arcs of material
visible in H{alpha} suggest indeed violent ejections of gas. In
contrast, H I synthesis observations revealed a rotating disc in a
dominant dark matter halo (Meurer, Staveley-Smith & Killeen 1998).

3. 2006ApJS..165..307M
Re:NGC 1705
HIPASS J0454-53 (NGC 1705).This is an amorphous/BCD galaxy well known for its
off-center super star cluster and strong galactic wind. Our H{alpha} image shows
minor-axis arcs, not seen by Meurer et al. (1992), which reach out to 90" to the
S, and 94" to the NNW.

4. 2003ApJS..146....1W
Re:NGC 1705
NGC 1705.-This is among the 10 sight lines with the highest S/N ratio
(23 per resolution element). Heckman et al. (2001) present a detailed
analysis of this sight line. The continuum placement is somewhat
difficult. We decided that the flux at 1034.5 {angstrom} represents the
continuum level. The implication of this choice is that there is
absorption at all velocities between the Galactic and HVC components at
0 and +325 km s^-1^. On the other hand, this velocity range may show
absorption associated with NGC 1705. Unfortunately, the continuum is too
complicated to check this using the O VI {lambda}1037.617 line. Heckman
et al. (2001) chose the continuum to be much lower and do not list the
intermediate (180 km s^-1^) component. This would imply a strong wiggle
and a sharp upturn at 1034 {angstrom}. This could be justified by
arguing that the O VI in NGC 1705 has a P Cygni profile. It would yield
an equivalent width of 180 +- 9 m{angstrom} between v = -70 and
105 km s^-1^ for the Milky Way (rather than 239 +- 15 between -120 and
120 km s^-1^) and of 120 +- 8 +- 9 {angstrom} between v = 265 and
400 km s^-1^ for the HVC component (rather than 200 +- 9 km s^-1^).
Half the difference between these values and the values derived from
the higher placed continuum is included in the systematic error.
The HVC absorption between 245 and 435 km s^-1^ is associated with HVC
WW 487 (Wakker & van Woerden 1991), which was also detected in several
other absorption lines by Sahu & Blades (1997).
The feature at 1033.816 {angstrom} (550 km s^-1^ on the O VI velocity
scale) is O VI associated with NGC 1705.

5. 1999ApJ...519...89C
Re:NGC 1705
NGC 1705.-Lamb et al. (1985) suggest that this dwarf galaxy is in a
starburst or post-starburst phase. NED lists its classification as an
H II region galaxy. We did not detect any compact X-ray sources in the
nuclear region of NGC 1705.

6. 1994CAG1..B...0000S
Re:NGC 1705
Amorphous
CD-140-S
Feb 1/2, 1978
103aO + GG385
50 min
NGC 1705 was classed as an S0 pec in both
the RC1 and the RC2 based on small-scale plates
taken at Mount Stromlo with the 30-inch
Reynolds Telescope. This classification is
inappropriate; the problem is caused by the high
surface brightness of the amorphous light, as
described in the paragraphs on NGC 5253 in the
middle column here.
The spectrum is rich in emission lines across
the entire disk (Sandage 1978). The strongest
lines are H{alpha}, H{beta}, and N1 and N2. Objects
presumed to be stars are embedded in the intense
disk light. They are numerous at B = 20, and the
brightest are undoubtedly brighter than this. The
color of the disk light is very blue. Robust
current star formation is occurring.

7. 1994CAG1..B...0000S
Re:NGC 1705
Amorphous
CD-145-S
Feb 2/3, 1978
103aO + GG385
20 min
The most curious feature in the image is the
presence of an intense blue object displaced from
the center by about a third the disk length. The
object has a hydrogen absorption spectrum showing
the same velocity as the disk emission. The
spectrum resembles those of the super star
clusters in NGC 1569 (Arp and Sandage 1985)
that have absolute magnitudes of M_B_ = -13.
The redshift of NGC 1705 is v_o = 445 km/s.
At the redshift distance of 9 Mpc (m - M = 29.8)
the compact blue object with an apparent
magnitude of B = 16 must have an absolute
magnitude of M_B_ = -14. Such super clusters are
known in NGC 625 (panel 336), NGC 1705
here, NGC 1569 (panel 336), and perhaps NGC 1140.
Spectra (Meurer et al. 1988, 1992) show
that gas is being expelled from NGC 1705 by
super-galactic winds created by the momentum
transfer of the photon energy from the super star
cluster to the gas. This is the characteristic
process in starburst galaxies and may be a
common feature throughout the Amorphous type.

8. 1993ApJS...86....5K
Re:NGC 1705
NGC 1705; Irr Am, BCDG.
Lamb et al. (1985) suggest that this blue compact dwarf galaxy is either
in a mild starburst phase or in a postburst phase. This irregular galaxy
has a steep radial gradient in surface brightness. Its low metallicity
resembles that of its neighbor, the LMC (Meurer et al. 1992). The strong
emission lines observed in the optical spectrum and the strong absorption
features in the UV spectrum of this galaxy are well accounted for by B0
and B1 stars of approximately 20 M_sun_, although this result does not
exclude a contribution from stars of higher mass assuming a normal IMF
(Lamb et al. 1985).
In a multi-wave-band study, Meurer et al. (1992) observe the presence
of two stellar populations coexisting in the galaxy: an inner high
surface brightness component, extending up to 500 pc from the center, and
a low surface brightness one, up to 1.5 kpc. The dichotomy may originate
from two bursts of star formation that arose at different times.
Alternatively, the dichotomy may stem from a difference in the IMF, with
the high brightness population being `richer in high-mass stars. H{alpha}
imaging reveals the presence of a bipolar outflow of gas, likely to
deplete the galaxy of a large amount of its gas supply.
NGC 1705 is a gas-rich BCG, and because of this, York et al. (1990)
argue that the ISM contributes Si IV {lambda}1400 and C IV {lambda}1550
absorption lines comparable to the stellar contribution.

9. 1985SGC...C...0000C
Re:NGC 1705
Plate 2819
Overexposed center, twisted lens with streamers and knots. Possible I0.

10. 1982ESOU..C...0000L
Re:ESO 045306-5326.5
=ESO 158- G 13
asymmetric
*multiple nuclei, or superimposed stars?

11. 1979AJ.....84..472S
Re:NGC 1705
Resolved into a few bright stars, across the face of a
high-surface-brightness, amorphous luminosity distribution
similar to NGC 0520, NGC 3077, M82, and NGC 5253.
Falls outside the Hubble classification system.
In addition to the resolved stars that begin near B = 20 mag,
an intense object at B = 15 mag is displaced froin the center
of the amorphous distribution.
Spectra of this object show hydrogen absorption lines and
other indications of an early-type spectrum.
The absolute magnitude of this intense object is M(B) = -15 mag, and
hence is not a single star but a cluster, or a super-association.

12. 1964RC1...C...0000d
Re:NGC 1705
Very bright nucleus, asymmetric wings?
Star (mag = 14.5) superposed.


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