Burst Bubble Nebula, or the Emerald Firebird (see next image), north of NGC 3572. Green: H-alpha 11 hrs, Blue: OIII 11 hrs, Red: SII 8 hrs, and NII 4 hrs, all in 1hr subs. 0.55 sec arc per pixel. Image height about 48 min arc, north up. Aspen CG16M on 20 inch PlaneWave.
