A Galaxy’s Orientation in Space
The orientation of a galaxy refers to the angle from which we
view it. For ellipticals, the orientation isn’t very important,
because an elliptical shape looks rounded from any viewing
angle. The viewing angle may determine just how rounded
it will appear. Spiral galaxies, on the other hand, look very
different depending on how you view them. When viewed “face
on,” spiral galaxies show their nice pinwheel shape, but when viewed “edge-on,”
spiral galaxies look like fried eggs viewed from the side. When viewed edge-on,
other features of the spiral galaxy come into view: the central bulge (the yolk of
the egg), the halo, and the disk where the spiral arms are located (the white of
the fried egg). Often a dark lane of dust can be seen in the disk. The orientation of
irregular galaxies isn’t important because they have no set pattern or structure.
A Galaxy’s Orientation in SpaceThe orientation of a galaxy refers to the angle from which weview it. For ellipticals, the orientation isn’t very important,because an elliptical shape looks rounded from any viewingangle. The viewing angle may determine just how roundedit will appear. Spiral galaxies, on the other hand, look verydifferent depending on how you view them. When viewed “faceon,” spiral galaxies show their nice pinwheel shape, but when viewed “edge-on,”spiral galaxies look like fried eggs viewed from the side. When viewed edge-on,other features of the spiral galaxy come into view: the central bulge (the yolk ofthe egg), the halo, and the disk where the spiral arms are located (the white ofthe fried egg). Often a dark lane of dust can be seen in the disk. The orientation ofirregular galaxies isn’t important because they have no set pattern or structure.
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