A prominent scientist once said that the universe is both unknown and unknowable. Consider the following astronomy in the known universe.

Quasi-stellar radio sources (quasars) are light sources that are relatively small, yet they produce more energy than a cluster of 10 trillion stars! Dr. Maarten Schmidt of the California Institute of Technology discovered them in 1963.

Supernovae are stellar explosions that suddenly increase their luminosity by more than 10 million times before fading from view over a period of several weeks or months.

A neutron star is a star that implodes. The gravitational forces crush the atoms into nuclear particles called neutrons. A neutron star would have an unbelievable density, as a teaspoon of its material would weigh a billion tons on earth. In fact, its weight would be sufficient to drive itself all the way through our earth. If the whole earth were compressed to the same density, it would be approximately 300 feet in diameter.

A black hole occurs when an imploding star continues beyond the neutron stage. Its gravitational forces thus become so strong that even light itself cannot escape. Dr. Kip Thorne of the California Institute of Technology describes the nature and effects of black holes:

A black hole is the end product of the catastrophic collapse of a really large star, the ultimate concentration of matter. . . . Anything it traps can never escape. The black hole can neither split nor decrease in size; it can only grow, and nothing can prevent it from growing. Ultimately if the universe itself does not collapse and die first, the black holes will eat up all the matter in our galaxy. Already, as much as one ten thousandth of the universe might be down black holes. (National Geographic, May 1974)

As an object reaches the speed of light, time slows down.

If a rocket ship manned by several men were to set out to explore the universe traveling at near the speed of light, not only would time on the spacecraft slow down, but its length and weight would also be affected. Imagine a spaceship measuring 1,000 feet in length and weighing 1,000 tons. At 162,000 miles per second, it would measure only 500 feet, but it would weigh 2,000 tons. It has furthermore been speculated that if a 30–year–old man could somehow remove himself to a planet exactly 30 light–years away from earth and point a telescope back to earth, he could actually watch himself being born.