Sharpless 101: the Cosmic Tulip Sharpless 101 is a H II region emission nebula located in the constellation Cygnus. It is popularly called the Tulip Nebula because it appears to resemble the outline of a tulip when imaged photographically. It was catalogued by astronomer Stewart Sharpless as Sh2-101 in his 1959 catalog of nebulae. It lies at a distance of about 6,000 light-years from Earth. Sh2-101, at least in the field seen from earth, is in close proximity to microquasar Cygnus X-1, site of one of the first suspected black holes. Cygnus X-1 belongs to a high-mass X-ray binary system, located about 6,070 light years from the Sun, that includes a blue supergiant variable star designated HDE 226868 which it orbits at about 0.2 AU, or 20% of the distance from the Earth to the Sun In the image below, red, green, and blue hues map emission from ionized sulfur, hydrogen, and oxygen atoms. 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 visible light emission from the Tulip Nebula. HDE 227018 is the bright star very near the blue arc at the center of the cosmic tulip. ► Image source>> https://apod.nasa.gov/apod/ap161020.html Image Credit & Copyright: Martin Pugh Further reading and references ► Cygnus (constellation)>> https://en.wikipedia.org/wiki/Cygnus_(constellation) ► OB associations>> https://en.wikipedia.org/wiki/Stellar_kinematics#OB_associations ► Cygnus X-1>> https://en.wikipedia.org/wiki/Cygnus_X-1 ► H II region>> https://en.wikipedia.org/wiki/H_II_region ► Sh2-101>> https://en.wikipedia.org/wiki/Sh2-101 ► Emission Nebula>> https://en.wikipedia.org/wiki/Emission_nebula #Universe, #TulipNebula, #CygnusConstellation, #EmissionNebula