An 8.8 Minute Orbital Period Eclipsing Detached Double White Dwarf Binary
Kevin B. Burdge et al 2020 ApJL 905 L7
Newly discovered ZTF J2243+5242 is only the second known eclipsing double white dwarf binary with an orbital period of less than 10 minutes. The binary, which will merge in ~400,000 yr, should be detectable by LISA.