I was collecting some fun facts for a southern sky tour tomorrow night, and I was pondering what was opposite the central hub of the Milky Way. In trying to convey one of the fun facts—that the farthest edge of the galaxy from Earth is 70,000 light years in the direction of the edge of the Great Sagittarius Star Cloud—I wanted to provide the contrast of the 30,000 light years to the edge opposite the core. I had no idea what was in that direction, so I fired up Stellarium and turned on the galactic coordinates grid. To my surprise, the point on the galactic plane opposite the core is almost at the center of the "Winter Hexagon" (winter in the Northern Hemisphere). But even more surprising was a ghostly nebula almost 4˚ across that looked a lot like a supernova remnant. A quick search of the Google found it: Simeis 147.
So to sum up the fun fact:
180˚ opposite the central hub of the Milky Way is the center of the Winter Hexagon asterism, the point where the constellations Auriga, Gemini, Taurus, and Orion meet. 8 arcminutes from the point lies the magnitude 8 star HIP 27088. The star also marks the edge of a Simeis 147, a supernova remant almost 4˚ wide from a star 3000 light years from earth that exploded 40,000 years ago.
Today I learned.