NASA/IPAC EXTRAGALACTIC DATABASE
Date and Time of the Query: 2019-06-25 T08:18:05 PDT
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Notes for object NGC 0784

4 note(s) found in NED.


1. 2000A&AS..142..425D
Re:NGC 0784
3.1 NGC 784 = UGC 1501 = PGC 7671 = IRAS 01582+2836
This irregular galaxy seen nearly edge-on with angular dimensions of
6.6' x 1.5' and an integral apparent magnitude of B_T_ = 12.23 has a
radial velocity of V_h_ = 198 km s^-1^ (NASA Extragalactic Database =
NED). In spite of its expected small distance, NGC 784 has not yet been
resolved into stars. Broeils & van Woerden (1994) studied the structure
and kinematics of NGC 784 in the H I line, showing that its neutral
hydrogen content as well as rotational amplitude are typical of an
irregular galaxy. The central part of NGC 784 is represented in Fig. 1
from our V CCD frame. Among star-like objects found by DAOPHOT in this
field we put into a Colour-Magnitude Diagram (=CMD) 84 stars, whose
image parameters satisfy the conditions |SHARP|< 2, |CHI|< 2, and
{sigma}(m) < 0.2^m^. The CMD for them, Fig. 2, shows the presence of
some blue stars. Following Sandage & Tammann (1974) and de Vaucouleurs
(1979) we estimated the distance modulus via the relation
(m - M)_0_ = 1.51 - 0.51 B_T_ - A_B_ + 4.14 (1) between the mean
apparent magnitude of three blue supergiant candidates, , and the
integral magnitude of the galaxy, B_T_, where A_B_ is the galactic
extinction. The numerical coefficients were derived by Karachentsev &
Tikhonov (1994) from galaxies with distances known via cepheids. In the
cases where a galaxy was observed in the V and I bands only, the (B-V)
color was derived from the relation (B-V)= 0.83*(V-I) defined by
the standard Landolt's stars with V-I < 1. With = 20.39 and
A_B_ = 0.22 we derive for NGC 784 a distance modulus (m - M)_0_= 28.47
or D = 5.0 Mpc.
Note that recent H I observations by Huchtmeier et al. (2000) reveal in
the NGC 784 neighbourhood two dwarf galaxies, kk16 and kk17, with radial
velocities +399 and +348 km s^-1^, respectively, which are probable
companions of NGC 784.

2. 1995ApJS...98..477H
Re:NGC 0784
No obvious nucleus can be identified in this diffuse galaxy. The central
knot has the spectrum of a high-excitation H II region, as do the remaining
knots along the slit.

3. 1994AJ....108.2128C
Re:PGC 007671
PGC 007671 = NGC 784. PA = 0.

4. 1973UGC...C...0000N
Re:UGC 01501
Companion 6.6, 160, 0.40 x 0.35, very high surface brightness


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