IC 342 is a nearby giant spiral (classified as SAB(rs)cd according to
the
NED) low-inclination (∼25°)
galaxy that lies along a line of sight through the Galactic plane
(l = 138° b = 10°), thus has a significant
light extinction by Galactic dust. The value of the extinction, however,
is matter of some debates with recent estimations of about 2 magnitudes
in visual wavelengths. Due to this IC 342 the most robust results
have been obtained on the basis of radio studies of its neutral hydrogen (HI)
and molecular gas components. For the same reason all the
photometric distance estimations are the subject of large uncertainty,
resulting to the astonishing discrepancy range, from 1.7 to 4.5 Mpc, that
is a really huge variance for such a nearby object.
While the exact size (angular size is more than 20°) and
mass of this galaxy is still subject of
controversy, there are strong indications (e.g. rotation velocity) that
in many respects IC 342 resembles giant spiral similar to our own
Galaxy. IC&nbps;342 competes
with two others nearest giant spirals,
Milky Way and Andromeda (M 31), for the gravitational influence
in the Local Volume. Together with its companion in the
group, nearest giant elliptical galaxy
Maffei 1, IC 342 might have played a significant role in the evolution of
the Local Group (e.g.,
Buta and McCall 1999,ApJSS, 124, 33).
Images of IC342 (colors are the RGB-combination of the V, R, and I bands), obtained by the author with the 6m BTA telescope (SAO, Russia).
| Field S1 Field S2 | Field S3 Field S4 Field S5 | ||
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| Field S6 | DSS-image with the field map | ||
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| Field S9 | Field S11 | Field KK35 | |
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| Radio | Hubble Space Telescope |
|---|---|
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| 1.44 GHz (21 cm; HI) image obtained with VLA. | Image of the central area of IC342, obtained with HST. |