Journal article Open Access
Ishibashi, Kazunori; Gull, Theodore R.; Davidson, Kris; Smith, Nathan; Lanz, Thierry; Lindler, Don; Feggans, Keith; Verner, Ekaterina; Woodgate, Bruce E.; Kimble, Randy A.; Bowers, Charles W.; Kraemer, Steven; Heap, Sarah R.; Danks, Anthony C.; Maran, Stephen P.; Joseph, Charles L.; Kaiser, Mary Elizabeth; Linsky, Jeffrey L.; Roesler, Fred; Weistrop, and Donna
We report long-slit spectroscopic mapping of the η Carinae nebula obtained using the Space Telescope Imaging Spectrograph. The observations reveal the presence of a previously unknown bipolar emission nebula (roughly ±2'' along its major axis) embedded within the well-known and larger Homunculus Nebula. A preliminary analysis suggests that this embedded nebula may have originated from a minor eruption event circa 1890, 50 years after the formation of the larger Homunculus.