Strongest Source of Gravitational Waves?

Stellar tango. These tightly orbiting white dwarfs, doomed to collide, churn space with gravitational waves in this artist's illustration.
CREDIT: NASA GSFC/D. Berry

At the American Astronomical Society meeting now under way in Minneapolis, Tod Strohmayer (NASA/Goddard Space Flight Center) reported on periodic X-ray pulsations from a source known as RX J0806.3+1527. The pulsations, found with the Chandra X-Ray Observatory, agree with earlier, visible-light observations indicating that the source is a pair of white-dwarf stars orbiting each other in a tight binary system. The two collapsed stars are separated by only 80,000 kilometers (50,000 miles, or one-fifth the Earth-Moon distance) and circle each other every 5.36 minutes. No known binary star has a shorter orbital period.

article in Sky and Telescope.

White Dwarfs in a Death Spiral in Science.