We report the discovery of a new ZZ Ceti star observed on the assumption that most DA stars with temperature near 11,000 K are pulsators and on a temperature determination using lUE data. Even though BPM 37093 had already been claimed as a nonvariable, it pulsates with a semi-amplitude of 4 mmag and a period of ~600 s, being the smallest amplitude ZZ Ceti star known to date.
The astrophysical journal. Chicago. Vol. 390, no. 2, pt. 2 (May 1992), p. L89-L91