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Accretion Disk

A rotating disk of gas, dust, and other matter that spirals into a central massive object like a black hole. The material heats up due to friction and gravitational forces, emitting radiation across various wavelengths.

Source: nasa.gov

APODs including "Accretion Disk"

The Tulip and Cygnus X-1

16/02/2017

The Tulip and Cygnus X-1
Image Credit: Ivan Eder / NASA APOD

Framing a bright emission region, this telescopic view looks out along the plane of our Milky Way Galaxy toward the nebula rich constellation Cygnus the Swan. 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. About 8,000 light-years distant and 70 light-years across the complex and beautiful nebula blossoms at the center of this composite image. 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. HDE 227018 is the bright star near the center of the nebula. Also framed in the field of view is microquasar Cygnus X-1, one of the strongest X-ray sources in planet Earth's sky. Driven by powerful jets from a black hole accretion disk, its fainter visible curved shock front lies above and right, just beyond the cosmic Tulip's petals