heic0516 — Science Release
Astronomers use Hubble to 'weigh' Dog Star's companion
13 December 2005: White dwarfs are important to theories of both stellar and cosmological evolution. New results published in the Monthly Notices of the Royal Astronomical Society provide for the first time an accurate measurement of the weight of the nearest white dwarf, Sirius B, companion of the brightest star in the sky. It turns out that Sirius's companion, despite being smaller than the Earth, has a mass that is 98% that of our own Sun.