Astronomy Picture of the Day . Barnard Stares at NGC 2170 . ... 19.01.2013 . ... Known as Barnard's loop , the structure is too faint to be seen with the eye, shaped by long gone supernova explosions and the winds from massive stars, and still traced by the light of hydrogen atoms. Barnard's loop lies about 1,500 light-years away roughly centered on the Great Orion Nebula , a stellar nursery along the edge of Orion's molecular clouds. ... Publications with keywords: emission nebula . ...