AAS Meeting #193 - Austin, Texas, January 1999
Session 69. Circumstellar Material
Display, Friday, January 8, 1999, 9:20am-6:30pm, Exhibit Hall 1

## [69.12] HST/STIS observations of Eta Carinae: Unexplained velocity structures near the star

K. Ishibashi (Univ. of Minnesota), K. Davidson (Univ. of Minnesota), T. R. Gull (NASA/GSFC/LASP), HST Cycle 7 GO Eta Carinae Team

Our HST/STIS imaging spectroscopic observations in March 1998 reveal two unexplained velocity structures moving in a polar direction within 2 seconds of arc (~ 5\times{103} A.U.) of the massive star \eta Carinae. One of the two flows shows a trace of bipolar'' plasma flow which resembles fast moving ejecta (~300 km/s) being slowed down by the existing circumstellar medium, while the other component illustrates ubiquitous, very slow moving ejecta of \sim -40 km/s at any position along the slit. Superposition of these two velocity components in the spectroscopic image shows a pattern which resembles an inverse-dollar'' sign, i.e., a dollar character  \$'' being flipped along the vertical bar. These velocity structures are quite unexpected and do not fit easily into previous ideas concerning the stellar wind.