Black Holes
Year of Discovery: 1916
What Is It? A collapsed star that is so dense, and whose gravitational pull is so
great, that not even light can escape it. Such stars would look like black
holes in a black universe.
Who Discovered It? Karl Schwarzschild
Why Is This One of the 100 Greatest?
Many consider black holes to be the ultimate wonder of the universe, the strangest of
all stellar objects. Black holes might be the birthplace of new universes, even new dimensions. Black holes might mark the beginning and end of time. Some consider them to be
possible time travel machines as well as a way to travel faster than the speed of light. Many
believe that black holes could be the ultimate future energy source, providing power stations throughout the galaxy.
Certainly, black holes were first a theoretical, and then a practical, great mystery of astronomy in the twentieth century. Their discovery led science a giant step closer to understanding the universe around us and provided a solid confirmation of Einstein’s theory of
relativity.
How Was It Discovered?
A black hole is not really a hole at all. It is a collapsed star that crushed in on itself. As
the star condenses, its gravity increases. If the collapsed star’s gravity becomes so strong
that not even light (particles traveling at light speed) can escape the gravitational pull, then
it will appear like a black hole (in the pitch black background of space).
Two men get the credit for the discovery of these bizarre and unseeable phenomena. The
first was German astronomer wonder-boy, Karl Schwarzschild. As a child, Schwarzschild
was fascinated by celestial mechanics (the motion of the stars), and he published his first two
papers on the theory of how double stars move when he was only 16 (in 1889). In 1900,
Schwarzschild presented a lecture to the German astronomical society in which he theorized
that space did not act like a regular three-dimensional box. It warped in strange ways, pulled
and pushed by gravity. Schwarzschild called it “the curvature of space.”
Five years later, Einstein published his energy equation and his theory of relativity,
which also talked of the curvature of space. In 1916, while serving in the German army on
the Russian front during World War I, Schwarzschild was the first to solve Einstein’s equations for general relativity. He found that, as a star collapsed into a single point of unimagin-
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