Happy Birthday, Robert Woodrow Wilson
This American astronomer was born on January 10, 1936, in Houston, Texas. He and a colleague (Arno Allan Penzias) shared a Nobel Prize for their discovery of the cosmic microwave background radiation.
They found the cosmic microwave background radiation? What the heck does that mean?
It means that Wilson and Penzias found evidence—the smoking gun, as it were—of the Big Bang!
Like so many other discoveries, the two radio astronomers made their discovery by “accident.” They detected a hiss that they couldn't explain, and they checked everything—even cleaning their radio telescope of pigeon droppings—in an effort to get rid of the sound. Finally they realized that the hiss was actually the previously predicted radiation left over from the Big Bang that started space and time and our universe.
That's right, we can detect the first photons—the oldest light in the universe! According to a science website, you and I can “see” this radiation, too, by looking at a TV with the cable disconnected, or a TV tuned to a channel it doesn't receive. About 1% of the static we see is the “ancient remnant of the Big Bang.”
The cosmic microwave background radiation is a faint background glow in the microwave portion of the electromagnetic spectrum. It's not associated with any star or galaxy, and this glow is almost exactly the same in every direction. When the universe was very young, before stars formed, it was smaller, and it was filled with white-hot hydrogen plasma. As the universe expanded, it grew cooler, and atoms and eventually stars and planets were able to form.
The leftover radiation from the ultra-hot Big Bag is now about 3 kelvins (way, way cold by Earth standards!) – just three kelvins (what we normally think of as " three degrees") above absolute zero.
To learn more about the Big Bang...