Black Hole NGC 4889

A black hole is a region of spacetime exhibiting gravitational acceleration so strong that nothing—no particles or even electromagnetic radiation such as light—can escape from it. The theory of general relativity predicts that a sufficiently compact mass can deform spacetime to form a black hole. The boundary of the region from which no escape is possible is called the event horizon. Although the event horizon has an enormous effect on the fate and circumstances of an object crossing it, no locally detectable features appear to be observed. In many ways, a black hole acts like an ideal black body, as it reflects no light. Moreover, quantum field theory in curved spacetime predicts that event horizons emit Hawking radiation, with the same spectrum as a black body of a temperature inversely proportional to its mass. This temperature is on the order of billionths of a kelvin for black holes of stellar mass, making it essentially impossible to observe.



Venus Square to Mars. Venus, the goddess of love, harmony and beauty is fighting with her lover Mars over their very different point of views. Venus is in Scorpio and wants deep commitment and honesty. Mars is in playful Leo and likes to play, seduce and tempt the goddess. Men are from Mars and women are from Venus and they are often very different if their perspectives, needs and desires. I always thought that book from John Gray was genius in playing on the deep archetypes we all have in us. Only recently have space missions begun to solve this beguiling Solar System mystery--that a small number of distant moons have been successfully hiding, from the curious eyes of astronomers, life-sustaining liquid water beneath secretive shells of ice. The very productive Cassini mission might attain some indirect information by analyzing the ring arc material--however, it is unlikely to come close to the little moon again before the mission ends in 2017.