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Recent optical and IUE spectra of the bright DAO white dwarf Feige 55 reveal large Doppler shifts due to orbital motion. These Doppler shifts have a period of 1.46 days with a semi-amplitude of 87 km/s. There is no photometric signature of any companion; J and K band photometry place an upper limit of approximately 0.1 solar masses on the mass of any main sequence companion. From the lower limit we derive for the companion, we conclude that the unseen component is a cooler, less luminous, degenerate star. The status of Feige 55 as a double-degenerate system has important implications for the recent suggestion by Bergeron et al. (1994), that low mass DAO stars are primarily the product of post-EHB evolution.
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