What happens if you move 33,000 light years along the Sun's spiral arm in the Milky Way?

If you travel along the local Orion Spur towards the constellation Cygnus, at 2000 light years you encounter the Cygnus Rift absorbing clouds which hide the light from the stars in the galaxy at greater distances from us. At a distance of 3,000 light years you encounter the leading edge of the Perseus Spiral Arm which the Orion Spur seems to be attached to in this direction. There are lots of luminous Orion-like star forming regions and supernova remnants in this region of space, along with many large molecular cloud complexes. At a distance of 9,000 light years or so, you exit the Perseus Arm and enter what seems to be the inter-arm void.

If you travel the other way, you encounter the Eta Carina star cluster at about 12,000 light years, and not a whole lot else in between. My galactic cartography is better towards Cygnus because I have studied this region in detail in my research. I do not really know a lot about the Carina direction.


Copyright 1997 Dr. Sten Odenwald
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