The universe is full of galaxies, most of them so distant
that they are invisible through amateur telescopes. Many galaxies can be
seen through small instruments, most as nebulous blobs. The brightest (excepting
our own Milky Way), are the Magellanic Clouds (visible only from tropical
and southerly latitudes) and the Andromeda Galaxy (M31) which is visible
to the naked eye on dark nights. There are a multitude of others: some
with no distinctive structure, others with interesting shapes or easily
picked out details. In photographs taken through large telescopes, most
areas of the sky are filled with extremely faint galaxies. Just think:
each of these is a star system comparable to our own Milky Way, containing
all the other types of objects listed here. The Galaxies
Database contains a good selection of the brighter galaxies, visible
in small to medium-sized telescopes.
|M81 (lower right) and M82 in Ursa Major.
These galaxies appear in the same low power field.
Higher powers can be used to zoom in on them separately.
The main classes of galaxies are spiral, elliptical, and
irregular. In most cases, the spiral structure of a galaxy will not be
apparent, and ellipticals have little structure to delineate anyway. The
detail you will be looking for is principally in the galaxy's shape: Is
it more or less round or elongated? Is there a bright nucleus? Can you
see any extensions which might be spiral arms? Are there faint and bright
zones or mottled textures within the visible disk of the galaxy?
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