Photograph by NASA/CXC/Michael Garcia and Stephen Murray, SAO
Neutron stars and the immense energy of black holes glow like celestial fireflies around the center of the Andromeda galaxy two million light-years from Earth. Such objects typically have a temperature of tens of millions of degrees Celsius. Chandra discovered a much "cooler" million-degree object (blue dot) about ten light-years from the center of the galaxy, perhaps a white dwarf undergoing nuclear burning on its surface. The yellow spot above the blue may be where hot gas is spiraling into the supermassive black hole at the heart of the galaxy. Chandra's sensitive eye also detected the diffuse glow (pink) of interstellar gas that extends for a thousand light-years across the galaxy's core.