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Date and Time of the Query: 2019-06-15 T17:04:43 PDT
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Notes for object NGC 5058

2 note(s) found in NED.


1. 2005A&A...429..115N
Re:NGC 5058
4.11 NGC 5058 (UGC 08345, MKN 786)
.
Deep images of this galaxy show two maxima (Fig. 11a) within a
common, extended LSB component, which at low surface brightness
levels displays an asymmetric, curved morphology (see the 25.5 R
mag/{square}" isophote in Fig. 11a).
.
NGC 5058 was previously classified as a galaxy pair (KPG 370;
Karachentsev 1972). The components of this pair (N and S, Tifft 1982)
are most likely identical to the maxima visible in Fig. 11a, as can
be inferred from their relative positions (projected separation 8.7"
at a position angle 12^deg^; Tifft 1982 for components N and S). We
therefore adopted the latter denomination (cf. the inset in Fig.
11a).
.
On contrast-enhanced NIR images, source N resolves into 3 distinct
regions (N1, N2, N3 in Fig. 11a). Fainter extensions emanate from
this central source to the north, and southwards, connecting with
source S. A third extension ("NW" in Fig. 11a) extends northwestwards
from the southern source S. New H{alpha} images by GMP03 show that
the SF activity peaks close to source S, and around a northeastern
component, detached from the central regions ("NE" in Fig. 11). The
same data reveal only weak H{alpha} emission along the NW extension,
suggesting that this feature is not mainly due to nebular emission.
.
Since NGC 5058 is located at a small angular separation (11.6^deg^)
from the center of the Virgo Cluster, redshift-based distance
determinations using Virgocentric infall models suffer from the
Triple Value Problem (Teerikorpi et al. 1992). An alternative
distance determination by the same authors, based on the Tully-Fisher
relation, yields a large distance of 37.7 Mpc, even outside the range
of values allowed within the uncertainties of the Triple Value
Problem (see Fig. 1 in Teerikorpi et al. 1992). We suggest that the H
I velocity width that these authors use, 118 km s^-1^, may be partly
enlarged by the southern component S, which, by its velocity
difference to component N (58 km s^-1^, Tifft 1982), might be a
kinematically distinct subunit of NGC 5058.
.
Dynamical distortions or even a past merger event in this galaxy
appear also possible in view of the peculiar shape of the isophotes
in the LSB regime, as mentioned above. Irregularities south of the
center of the galaxy are traceable down to the limits of the J band
data (~24 J mag/{square}"). These condensations in the southernmost
outskirts of the galaxy show no obvious H{alpha} emission (GMP03).
.
We adopt here a distance D=11.6 Mpc, using the velocity of NGC 5058
with respect to the center of the Virgo Cluster (see N03) and H_0_=75
km s^-1^ Mpc^-1^; note that also for much larger distances, up to D <~
31.1 Mpc, the resulting absolute magnitude would be >-18 B mag, still
qualifying NGC 5058 as a BCD.
.
In view of the complex morphology at all surface brightness levels,
and of wide-spread SF activity and further condensations, a
decomposition of the surface brightness profiles is rendered
problematic. For R^*^ >21.6" i.e. outside strong irregular emission
in the J images, the SBPs can be approximated by an exponential,
albeit with some systematic differences (Fig. 11b). The SBPs suggest
however the presence of a type V SBP at large radii. An example
decomposition by means of a med is shown in Fig. 11b. The parameters
of this function cannot be reliably constrained, given the extended
influence of irregular and starburst emission, and the low S/N levels
(\mu _J~ 22 ... 23 mag/{square}") at which we suspect the flattening
occurs. The results of the profile decomposition given in Table 2
therefore refer to the exponential fit to the LSB host.

2. 1973UGC...C...0000N
Re:UGC 08345
Companion 2.4, 93, 0.4 x 0.4, E-S0


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