By Ron Cowen
From Minneapolis, at a meeting of the American Astronomical Society
Locked in a deadly embrace, two white dwarf stars may be the strongest source of gravitational waves now flooding our galaxy. The stars appear to be separated by just one-fifth the Earth-moon distance.
New X-ray observations of the duo, which resides roughly 1,600 light-years from Earth, indicate that the dwarfs take just under 5.5 minutes to orbit each other and are the most-compact binary-star system known. NASA’s Chandra X-ray Observatory also found that the pair’s orbital period is declining by 1.2 milliseconds each year.