... Credit Copyright: Terry Hancock (Down Under Observatory) Explanation: This rich starscape spans nearly 7 degrees on the sky, toward the Sagittarius spiral arm and the center of our Milky Way galaxy. ... With wingspans of 100 light-years or so, they shine with the telltale reddish glow of hydrogen atoms from over 5,000 light-years away. Colorful open star cluster M25 near the upper left edge of the scene is closer, a mere 2,000 light-years distant and about 20 light-years across. ...