The use of the COME-ON+ adaptive optics system has allowed us to resolve the dust shell of five late-type stars in the near infrared. These observations, all in agreement with previous high angular resolution ones, clearly show that aspherical dust shell is a common feature of the late stages of stellar evolution, as already concluded from polarization measurements (Johnson & Jones 1991).
The gap between the range of angular resolution from to allowed by infrared adaptive optics and the range below allowed by long baseline interferometry is now disappearing. This leads to a better understanding of both the post-AGB phase, where the dust shells are often extended and generally thick, and the AGB one, where a more tenuous shell is found to be closer to the star.
© European Southern Observatory (ESO) 1998
Online publication: September 8, 1998