1997A&A...325..609O

We present the first diffraction-limited speckle-masking bispectrum observations of the central part of the Red Rectangle at optical wavelengths (λ∼656nm and λ∼800nm). The results confirm infrared observations which show that the object is a bipolar nebula. The dark lane separating the two lobes is probably produced by an obscuring dust disk slightly inclined with respect to the line of sight. The fainter northern lobe appears not to be reddened by the disk. This implies an upper limit of the outer disk radius of about 200AU. We propose that the observed nebula is the result of recent mass ejection induced by unstable mass transfer from an AGB star to a close companion.