NGC 3199 lies about 12,000 light-years away, a glowing cosmic cloud in the southern constellation of Carina. The nebula is about 75 light-years across in this haunting, false-color view. Though the deep image reveals a more or less complete ring shape, it does look very lopsided with a much brighter edge at the lower right. Near the center of the ring is a Wolf-Rayet star, a massive, hot, short-lived star that generates an intense stellar wind. In fact, Wolf-Rayet stars are known to create nebulae with interesting shapes as their powerful winds sweep up surrounding interstellar material. In this case, the bright edge was thought to indicate a bow shock produced as the star plowed through a uniform medium, like a boat through water. But measurements have shown the star is not really moving directly toward the bright edge. So a more likely explanation is that the material surrounding the star is not uniform, but clumped and denser near the bright edge of windblown NGC 3199 (text adapted from APOD). Apo TEC140 (140/f7.2) - FLI Proline 16803 - Ha (165m) OIII (210m) R (60m) G (50m) B (50m) - Warrumbungle Observatory, Coonabarabran, NSW, Australia
An intriguing and beautiful nebula, NGC 3576 drifts through the Sagittarius arm of our spiral Milky Way Galaxy. Within the region, episodes of star formation are thought to contribute to the complex and suggestive shapes. Powerful winds from the nebula's embedded, young, massive stars shape the looping filaments. Hydrogen and oxygen, energized by intense ultraviolet radiation, contribute to the nebular glow. But the glow also silhouettes dense clouds of dust and gas. For example, the two condensing dark clouds near the center of the picture offer potential sites for the formation of new stars. NGC 3576 itself is about 100 light-years across and 9,000 light-years away in the southern constellation of Carina, not far on the sky from the famous Eta Carinae Nebula. At the left of the picture is NGC 3603, a much larger but more distant star forming region (text adapted from APOD). Apo TEC140 (140/f7.2) - FLI Proline 16803 - Ha (240m) OIII (270m) R (100m) G (110m) B (140m) - Warrumbungle Observatory, Coonabarabran, NSW, Australia