With its vast dimensions alone (being so close to us in space at a "mere" 2.3 million light years!), this object is one of the most imposing available to us (Figure 7.2). Surprisingly, in the telescope, it may at first prove to be a major disappointment; how could something so huge and bright still reveal so little of its true nature to us? While it is unfortunate that much of our first reaction is well founded, once we realize that it is not going to reveal itself fully to us in real time (particularly from our city locations), there are nevertheless numerous features to explore. With experience, you may be able to discern something of the large dust lane between its core and spiral arms, and possibly the bright southern star cloud so evident on photographs. If you arm yourself with a detailed chart, you also may be able to detect some of the globular clusters that encircle the galaxy, a b
Figure 7.2. NGC 224 (M31): a the nucleus of the galaxy; video frame: intensifier. b This image intensifier-color view of the core region of M31 is reproduced courtesy of W.J. Collins of Collins Electro Optics. It was taken from suburban Denver in a 6-second exposure using a digital camera, in conjunction with Collins' 7-inch Astro-Physics refractor, equipped with his company's I3 Piece image intensifier. The dust lanes mentioned in the text are clearly visible, providing some expectation of the live intensified view with low powers (especially using the Collins unit), from a location with low humidity and high sky transparency.
in the same way as do those in the Milky Way; these require patience and viewing skills, as they appear more like star-like points. The sheer size of this galaxy in the eyepiece view needs to be fully appreciated (far exceeding the field of view for most telescopes, even at low power), making the identity and whereabouts of its main companion elliptical galaxies NGC 205 and NGC 221 (M32), hard to fathom. NGC 205 is much further away from the central core of M31 than you may realize; because it is not as bright as NGC 221 it is also harder to detect. Far in the future, all three will collide with the Milky Way, in a great cosmic interplay that will forever change their shapes and even result in the obliteration of some.
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