Why Is The Sky Blue?

In order to understand why the sky is blue, you must first learn a bit about the properties of light. While the light from the Sun or an artificial source such as a light bulb may look white, it’s actually composed of many colors. A rainbow displays those colors by splitting the light through water droplets in the air. All of those colors, when combined, appear to be white.

You’ve probably heard the term “light wave”. Each of the colors that make up the white light have a different wavelength. It’s not necessary that you totally understand this in order to understand why the sky is blue. Just so you know that the different colors have different properties (wavelengths).

Waves can be affected by the world around them. Light waves can be reflected. That’s why you can see your “reflection” in a mirror. Light waves are reflected off your face, then reflected off the mirror’s surface, and then back to your eyes and you see yourself!

Waves can also be absorbed. Light waves can be absorbed by the gas molecules in Earth’s atmosphere. We mentioned earlier that the different colors in light have different wavelengths. Some wavelengths are absorbed by the atmosphere better than others. Therefore, some of the colors pass through the atmosphere (sky) and some are absorbed.

The color whose wavelength is most readily absorbed just happens to be blue! The other colors of sunlight pass straight through the atmosphere and illuminate the surface of the Earth and everything on it. The blue light, however, after being absorbed by the gas molecules, re-radiates away from them in all directions. So when you look at the sky, it is literally “shining with blue light”.

To put it in very simple terms … the sky is blue because it absorbs the blue light from the Sun while letting the other colors pass through.

So what makes a sunset look red or orange? Is the atmosphere absorbing orange lightwaves? The answer is no. The same effect that causes the sky to be blue causes a sunset to appear red or orange. Let’s look at how that occurs.

When you look at a sunset, you’re not looking at the sky … you’re looking at the Sun. You’re seeing the light waves that are least absorbed by the molecules in the atmosphere. The ones that pass through and make it to your eyes. The color that is least absorbed just happens to be red. As the Sun gets lower and lower in the sky, its light passes through more and more of the atmosphere before reaching your eyes. That results in not only more and more of the blue light being absorbed … the molecules start absorbing more and more of the other colors too. If you see the sunset in the flatlands where its light is passing through a maximum amount of atmosphere, all of the lightwaves are being absorbed more and more than the red ones. That’s why the color of the sunset changes as it gets lower in the sky!

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Who Invented Velcro?

It’s widely believed that Velcro was developed by NASA for the space program but that’s a myth. Velcro was actually invented in 1941 by George De Mestral, an engineer from Commugny, Switzerland. George and his dog were hunting in the Alps when George noticed something that most of us have experienced. There were dozens of these little sticky seeds all over his pant legs in in his dogs hair.

What George noticed that we didn’t was that while the seeds were nearly impossible to get out of his dog’s hair, it was relatively easy to remove them from his pant legs even though they were very firmly attached. Upon looking at the seeds with a microscope, George discovered that the sticky outer surface of the seeds was actually a huge number of “hooks” that got hooked to anything with a loop.

In a way, it’s not clear whether we should ask “Who invented Velcro” or “Who discovered Velcro”. Of course, even though something exists in nature, it’s seldom convenient to use in its natural form and the discoverer / inventor” deserves much credit for seeing the potential for making human life easier.

What if a product could be made that allows someone to open or close things in the snap of two fingers? Instead of tying shoelaces, for example, how about just snapping them “tied” in a moment? What about the possibility of hanging things on walls without having to puncture the wall? What about clothing that needs to go on and come off in a hurry such as a fireman’s heat resistant suit? There could be dozens or hundreds of such uses!

All George had to do was figure out a way to produce two simple items. He needed one layer of “hooks” and another layer of “loops” that were attached to something that could be sewn, glued, or in some other way attached to the walls, shoes, fireman’s suit, etc. For that he needed funding but, unfortunately, sometimes the inventor is the only one who sees that potential for his idea. Bankers couldn’t see the need for a product that filled a need that was already being performed by zippers and buttons. Of course, the bankers had made the same argument against the zipper just three decades earlier. Many people in the business community thought he was a fool for wasting his time on such an unneeded idea.

George didn’t give up though. He decided to do research on his own and with the help of a weaver from France to find an economical way to produce his “hooks” and “loops”. George nearly gave up when eight years later he had a brainstorm! He suddenly knew how to produce the product by machine in large quantities at a low cost!

In 1951 George Mestral received a patent for his invention. Very soon afterwards, Velcro was being sold in numerous locations in the US and around the world. Yes, George got the last laugh on the bankers and the business moguls and today Velcro is its own multi-million dollar per year success story!

Perhaps the most interesting reference to Velcro is the fact that it’s often blamed for the deaths of astronauts Gus Grissom, Edward White II, and Roger Chaffee during a test of the Apollo 1 spacecraft. Engineers had warned that Velcro, while extremely handy in space for keeping objects from floating around, was also dangerously flammable in an oxygen rich atmosphere. The Apollo 1 spacecraft contained a 100% oxygen atmosphere. Those engineers recommended no more than 500 square inches be installed but Velcro was so useful that the spacecraft ended out with ten times that much! In any case, it was the excessive use of Velcro along with the increased flammability of everything else in a pure oxygen atmosphere plus a spark from an electrical problem that cause the deaths. Velcro’s inherent flammability was only a small part of the problem.

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Who Invented the Television?

Philo Farnsworth showing off his invention for the first time (1928)

As with many inventions, more than one inventor was working on the television nearly simultaneously. This often creates controversy as to who the actual inventer was and that is definitely the case with the television. In this particular case, the controversy was hotly debated during the “cold war” as one of the inventors was Russian born (although he did become a naturalized U.S. citizen the year after filing his patent) while the other was a farm boy from the state of Utah. So who invented the television? A son of socialist Russia or a true blue capitalistic American?

The Russian-born inventor’s name was Vladimir Zworykin. His contribution to the development of the television was extremely important. He was the first person to file a patent application for an electron scanning tube. He called his an “iconoscope” and it was the basis for picture tube type television sets that are still used to this day! The problem with Zworykin’s patent was that the device itself never actually worked! The theory behind it was sound, however and he was the first one to patent the idea.

The U.S. inventor’s name was Philo Farnsworth. His contribution was that he actually got television to work, using his own version of an electron scanning tube. He did so by displaying the world’s first television picture on September 7, 1927. Philo Farnsworth went one step further in his claim to have invented the television, however, as he stated that he had the idea for that tube independently and considerably earlier than Vladimir Zworykin’s patent. In other words, he said that he hadn’t simply improved on Zworykin’s design.

To add to the “cold war” controversy mentioned earlier, Zworykin had filed for his patent in 1923 but did not become a naturalized U.S. citizen until 1924. Therefore, he was still Russian at that time! So the argument (which continues to this day) is not simply over who invented the television, but also, which nation gets the credit!

In 1930, Philo Farnsworth was granted a patent for his electron scanning tube. In his case, a working model was provided with his patent application. Also in 1930, Vladimir Zworykin visited Farnsworth’s laboratory and copied his design. Zworykin was not able to get his “copy” working until 1934, however, and could not get a patent for that version until 1938. Even then, the quality of the picture was horrible and his employers even ordered him to “move on” to something more productive!

A law suit was initiated in 1938 between Zworykin (and RCA who now employed him) and Farnsworth over who invented the television. During the suit, Farnsworth’s high school teacher testified that Farnsworth shared the basis for his scanning tube at the tender age of 14, thus confirming Farnsworth’s claim to having the idea first. Of course, we’ll never know to what, if any, extent that testimony was true. The “cold war” aspect at the time would have been a great motivator for a “good” American to want to help claim the invention for his country. Or, of course, the teacher may have been totally honest in their recollection.

Anyway, Philo Farnsworth won the suit against the corporate giant (RCA) and the Russian. RCA was forced to pay him royalties starting in 1939. In other words, the court ruled that Farnsworth was the one who had invented television. Again, of course, we must keep in mind that was a U.S. court!

So, in conclusion, it would seem that in order to determine who invented television, we would have to determine the following things:

1. Who actually first developed the theory behind the operation of the electron scanning tube?

2. Does Zworykin’s 1923 patent get precedence or does Farnsworth’s working model and 1938 court ruling?

3. Are the two inventors contributions both substantial and therefore, should they be considered co-inventors?

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Who Invented the Radio?

If you think that what you learned about who invented the radio at school was just enough for you to come to terms with the fact that there was just one person involved, then you surely are mistaken. Despite the fact that most of us learned in school that there was just one person involved, there are quite a few candidates to whom the credit has to be given for inventing the radio. If you wish to know about the list of people who invented the radio, then here it is for you.

Guglielmo Marconi was an Italian inventor who was the first person to actually show the practical usage of radio. He was the first person who sent out and received radio signals in 1895. Later in 1899 he sent out a radio signal across the English Channel and in 1902 he successfully had the letter S telegraphed from England to Newfoundland. These might seem like minor accomplishments but all great developments begin with a wimper.

In 1892, Nikola Telsa came up with the basic design for a radio. He was also responsible for patenting a robot boat in the year of 1898. In 1894 Alexander Popov created the world’s first radio receiver with a coherer, which was simply a tube with two closely spaced electrodes that could detected the presence of a radio signal but could not convert it to audio. This did, however, allow messages to be sent in morse code via radio signals for the first time! The day of its launch is still being commemorated in Russia as the Radio Day. Though the coherer was in radio reception use for a very long time, it was Sir Oliver Lodge who actually perfected the device.

In 1900, Reginald Fessenden was responsible for sending out the first radio based audio transmission. In 1906, the very first two-way radio communication commenced and in the same year the very first radio broadcast of both music and entertainment took place.

Among all these people who invented the radio, Heinrich Hertz is still well remembered since his name is used as the metric for all radio frequencies. He was the first German scientist who proved the existence of electromagnetic waves. He constructed a system that detected ultra high frequency radio waves. Hertz as a metric system became internationally recognized in 1933.

The other notable people who invented the radio were Nathan Stubblefield, Amos Dolbear, Mahlon Loomis and James Clerk Maxwell. Though the actual invention of the radio cannot be attributed to these names, they did significant research with radio waves and contributed to the field of science and technology.

With the help of radio transmission, Amos Dolbear was able to patent the first telegraph through wireless radio communication in 1882. Mahlon Loomis on the other hand was actually called the first wireless telegrapher since he was able to construct a communication system that transmitted information wirelessly between two sites that were 18 miles away from each other.

In all honesty, is believed that Nathan Stubblefield invented the radio even before Marconi or Telsa. He was the first person to have invented wireless transmission of the human voice through audio frequency induction. Maxwell on the other hand was the person who actually conceptualized the existence of radio waves.

So as with most inventions, many small discoveries were necessary in order to arrive at the radio we enjoy today! It’s rare when only one inventor is responsible for the entire project.

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