Far, far away, so far that the light we see today started its journey 2.2 million years ago, is an ordinary galaxy about the size our Milky Way galaxy.  At it's center is a black hole, like in the Milky Way galaxy.  It's central region looks like this:

Although in this image the galaxy, called M31, looks like the "foreground" stars in our Milky Way galaxy, it really covers a larger area of the sky.  To see more of it we must use a longer exposure.

If you look closely you can see a faint spiral arm structure.  You can't see it?  Ok, let's increase the exposure.

Narrow dark lanes separate wide spiral arms to the upper-left of the bright central region.  To the upper-right is a dark lane with detailed structure, and farther out from it is another spiral arm.  Let's increase the exposure once more.
 

Figure 1.  The image of the central region of the Andromeda Galaxy was made with a Meade Pictor 416XTE CCD imager, a Meade LX200 10-inch Schmidt-Cassegrain telscope, and an f/3 Focal Reducer/Field Flattener, yielding an effective focal length of 27 inches and an effective f-ratio of f/3.00.  This is the average of six 20-second exposures, with another set of six 20-second "reference" images taken for subtraction of the CCD's thermal noise.  Since the Pictor CCD imager has a "pixel depth" of 16 bits (65,536 gray levels), it is possible to produce many versions of the same image for display on a monitor, where each rendition emphasizes a particular small range of light levels.  All previous images were made in this manner, and are derived from the image shown here. The image width is 34 'arc, which is slightly larger than the diameter of the average full moon (31'arc).

Figure 2.  Three 20-second images of a region to the lower-right of the previous image.  The darkest lane in the previous image is now accompanied by an outer dark lane, defining three spiral arms.

Figure 3.  This is an average of 15 20-second images (equivalent to a well-guided 5-minute exposure) of a region below the previous image, taken on a different date, 2000.10.27/28.  In the upper-middle is a bright region within a spiral arm (perhaps a region of new star formation).  Note the delicate dark lanes that obscure starlight from behind them.

Figure 4.  The previous images is joined with a shorter exposure image taken to its north (of the same region as Fig. 2).

Figure 5.  This is the opposite end of the galaxy, the upper-left third.  Two imaged areas were joined together to produce a coverage of 34 x 57 'arc.

Figure 6.  Mosaic of 15 image areas, using 204 exposures (including the "reference" ones) taken over a 3-hour period, October 22, 2000.  Two satellite galaxies of this large galaxy are visible, one directly to the south (NGC 221) and the other to the upper-right (NGC 205).  The borders where images were joined are due to slight differences in manual adjustments of contrast and brightness.  All the "stars" visible in this image are in the "foreground" - meaning that they are within our Milky Way galaxy.  (North is at the top.)
 

Figure 7.  This mosaic serves two purposes: 1) it shows the immense size of the galaxy by inserting a full moon image having the same scale as the galaxy, and 2) it shows how much my "technique" for making mosaics has improved in just two observing nights.  This mosaic was my first attempt at joining images, and it illustrates the bad things that can happen when 1) the CCD imager is not aligned north-south accurately, 2) "flat field" corrections are not performed, 3) pixel artifacts are not properly aligned during the "dark frame" subtraction (not apparent in this greatly reduced scale version), and 4) thin clouds vary the sky brightness during an observing session.  The Andromeda Galaxy has its own unique challenges for the CCD photographer.  Film photography is better for rendering the overall image.

__________________  Images in next section are a zoom sequence, starting from a wide angle view  ______________________

Figure 8.  This wide angle picture shows M31 as part of the constellation Andromeda (two sets of lines emanating from a bright star in constellation Pegasus, in lower-right).  This image is 38 degrees wide.  [Nikon F3, 50 mm FL lens, f/2.8, mounted to Meade ETX125 telescope for guiding, 2.4-minute exposure, Fujicolor 800, 2001.09.18, Pine Mountain, 6000 ft, Ventura County, north of Ojai, CA.)

Figure 10.  Zoom 12x.  [Megrez 80 telephoto lens, 80 mm FL, f/6.0, Fujicolor Superia X-tra 800, average of 12 images totaling 73 minutes of exposure time, 2001.10.09 and 2001.10.13, Santa Barbara, CA]
 

[Stay tuned for more images of zoom sequence.]
 
 

_______________ Image below is by an advanced amateur ______________________________

Figure 11.  Here's a much reproduced film photograph taken by serious amateur Jason Ware.  He used a Meade 6-inch refractor with Fuji HG400 film, exposing for 90 minutes. (I've rotated the image to put north at the top.)  Note the bright region in a spiral arm near the lower-right edge.  This is the same one seen in my Fig. 3 image.

The Andromeda Galaxy, M31, is approaching our Milky Way galaxy with a speed of 300,000 miles per hour.  It is estimated that our two galaxies may collide in 3 billion years (Science, January 7, 2000, pg 64).  This could cause some stars to be "flung" away from their galaxy, condemned to roam empty intergalactic space forever.  Presumably, if this happened to our sun, the solar system would go with it.

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This site opened:  October 24, 2000.  Last Update:  October 17, 2001