Astronomy Picture of the Day

Explanation: When can you see a black hole, a tulip, and a swan all at once? At night -- if the timing is right, and if your telescope is pointed in the right direction. Cataloged as Sh2-101 and popularly called the Tulip Nebula, the reddish glowing cloud of interstellar gas and dust is also found in the 1959 catalog by astronomer Stewart Sharpless as Sh2-101. Nearly 70 light-years across, the complex and beautiful Tulip Nebula blossoms about 8,000 light-years away toward the constellation of Cygnus the Swan. Ultraviolet radiation from young energetic stars at the edge of the Cygnus OB3 association, including O star HDE 227018, ionizes the atoms and powers the emission from the Tulip Nebula. Also in the featured field of view is the black hole Cygnus X-1, which is also thought to be a microquasar because it is one of strongest X-ray sources in planet Earth's sky. Blasted by powerful jets from a lurking black hole, its fainter bluish curved shock front is only faintly visible beyond the cosmic Tulip's petals, near the right side of the frame.