02-20-2017, 08:52 AM
Technically we live in the Orion Arm (or Spur), rather than Orion's Arm, so the name is a little idiosyncratic. The Orion OB complex is probably the most prominent feature of our spur, so it is a reasonable name for this region; there may be other features along the length of the spur that are equally spectacular, but we can't see them as well because of intervening dust.