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Black Hole

A black hole is an astronomical object whose gravity is so strong that nothing—even light—can escape from within its event horizon. It forms when a massive star’s core collapses or through other processes, and may have an accretion disk of infalling matter that emits radiation. Supermassive black holes at galaxy centers influence stellar orbits, and mergers produce gravitational waves.

Source: nasa.gov

APODs including "Black Hole"

Cygnus and the Solitary Tree

18/03/2026

Cygnus and the Solitary Tree
Image Credit: 2025 Horacio Lander / AstroHoracio Text: Keighley Rockcliffe (NASA GSFC, UMBC CSST, CRESST II) / NASA APOD

A lone tree stands in a quiet meadow in Guadalajara, Spain, silhouetted against the Cygnus region rising above like flames in the night sky. This deep night skyscape is a composite of exposures that reveals a range of brightness and color human eyes can't quite see on their own. Spanning over a thousand times the angular size of the full moon, Cygnus sets the sky afire with active star formation where clouds of gas and dust collapse under gravity until nuclear fusion ignites and new stars are born. These stars ionize the surrounding hydrogen gas, causing it to glow crimson, while tendrils of interstellar dust absorb some of that light and cast dark shadows across the sky. Cygnus is a trove of celestial treasures, notably the Veil, Crescent, and Pelican nebulae, as well as Cygnus X-1, the first confirmed black hole. Cygnus continues to yield fresh science, including a new three-dimensional model of the Cygnus Loop made possible by the Chandra X-ray Observatory. Almost Hyperspace: Random APOD Generator