Chandra Release - November 21, 2016 Visual Description: Cygnus X-3 The image of the Cygnus X-3 stellar nursery showcases two glowing but irregular spots in shades of red, blue, purple and white. The composite includes X-rays from NASA's Chandra X-ray Observatory (colored in purple and white) and radio data from the Smithsonian's Submillimeter Array (red and blue). The X-ray data reveal the bright X-ray source to the right known as Cygnus X-3, a system containing either a black hole or neutron star (a.k.a. a compact source) left behind after the death of a massive star. Within that bright source, the compact object is pulling material away from a massive companion star. Astronomers call such systems "X-ray binaries." Chandra's high-resolution vision in X-rays also identifies a mysterious source of X-ray emission located very close to Cygnus X-3 on the sky (a smaller white object to the upper left). The separation of these two sources is equivalent to the width of a penny about 800 feet away. A decade later, astronomers reported the new source is a cloud of gas and dust. In astronomical terms, this cloud is rather small - about 0.7 light years in diameter. Astronomers realized that this nearby cloud was acting as a mirror, reflecting some of the X-rays generated by Cygnus X-3 towards Earth. They nicknamed this object the "Little Friend" due to its close proximity to Cygnus X-3 on the sky and because it also demonstrated the same 4.8-hour variability in X-rays seen in the X-ray binary.