Page 44 - cosmos4
P. 44
The idea of a body so massive that even light could not escape was briefly
proposed by astronomical pioneer and English clergyman John Michell in a letter
published in November 1784
Where are black holes?
A black hole is a region of spacetime where gravity is so strong that nothing—no
particles or even electromagnetic radiation such as light—can escape from it. A black
hole is anything but empty space. Rather, it is
a great amount of matter packed into a very
small area - think of a star ten times more
massive than the Sun squeezed into a sphere
approximately the diameter of New York City.
About 800 million light-years away, a black hole
devoured an unidentified object, and the resulting cosmic merger released enough
energy to wrinkle the fabric of space-time. These wrinkles, called gravitational waves,
travelled through the universe and eventually washed over Earth on August 14, 2019.
