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"
Hitomi Launches
18/02/2016
On February 17 at 5:45pm JST this H-IIA rocket blasted skyward from JAXA's Tanegashima Space Center located off the southern coast of Japan, planet Earth. Onboard was the ASTRO-H X-ray astronomy satellite, now in orbit. Designed to explore the extreme cosmos from black holes to massive galaxy clusters, the satellite observatory is equipped with four cutting-edge X-ray telescopes and instruments sensitive to photon energies from 300 to 600,000 electron volts. By comparison, visible light photon energies are 2 to 3 electron volts. Following a tradition of renaming satellites after their successful launch, ASTRO-H has been newly dubbed "Hitomi", inspired by an ancient legend of dragons. Hitomi means "the pupil of the eye".