Edge-on spiral galaxy NGC 891
Tags: galaxy, spiral, dust, NGC 891
If we could view the Milky Way from a distance of about 30 million light
years it would look something like NGC 891. But galaxies that look like
this are quite rare because the chance alignment of the thin disk of a
spiral galaxy with our line of sight is unusual. A few degrees either
side of its orientation and NGC 891 would be just another highly
inclined spiral galaxy.
From this unusual vantage point we can see in NGC 891 the surprising
narrowness of the obscuring dust lane, a dark, slightly irregular band
across the galaxy. We also see that it is yellowish, confirming that it
is dust, which absorbs blue light, as in the Milky Way. Also similar to
the Milky Way is the prominent central 'bulge' corresponding to the rich
star clouds in Sagittarius. However, unlike the Milky Way, NGC 891 is
relatively isolated, undisturbed by neighbouring galaxies. If this was a
distant view the Milky Way, the dust-lane would probably be distorted by
interaction with the Magellanic Clouds, which would be prominent in the
Photograph made from plates taken in October, 1991.
Top left is NE. Image width is about 10 arc min.
Credit: David Malin
© 1991-2002, David Malin/IAC/RGO (or David Malin/Instituto de Astrofisca des Canarias/Royal Greenwich Observatory)